Organic light-emitting device

ABSTRACT

An organic light-emitting device includes a first electrode; a second electrode; an organic layer between the first electrode and the second electrode, the organic layer including an emission layer, and an electron transport region between the emission layer and the second electrode. The emission layer includes a first compound represented by Formula 1 and a second compound represented by any one of Formulae 2-1 to 2-5. The electron transport region includes a third compound represented by Formula 7. The organic light-emitting device may have low driving voltage, high efficiency, and a long lifespan.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of Korean PatentApplication No. 10-2014-0195398, filed on Dec. 31, 2014, in the KoreanIntellectual Property Office, the entire content of which isincorporated herein by reference.

BACKGROUND 1. Field

One or more aspects of embodiments of the present disclosure aredirected to an organic light-emitting device.

2. Description of the Related Art

Organic light emitting devices are self-emission devices that have wideviewing angles, high contrast ratios, short response times, andexcellent brightness, driving voltage, and response speedcharacteristics, and can produce full-color images.

An organic light-emitting device may include a first electrodepositioned on a substrate, and a hole transport region, an emissionlayer, an electron transport region, and a second electrode,sequentially positioned on the first electrode. Holes provided from thefirst electrode may move toward the emission layer through the holetransport region, and electrons provided from the second electrode maymove toward the emission layer through the electron transport region.Carriers (e.g., holes and electrons), are recombined in the emissionlayer to produce excitons. These excitons change from an excited stateto a ground state, thereby generating light.

SUMMARY

One or more aspects of embodiments of the present invention are directedto an organic light-emitting device.

Additional aspects will be set forth in part in the description whichfollows and, in part, will be apparent from the description, or may belearned by practice of the presented embodiments.

In one or more embodiments of the present invention, an organiclight-emitting device includes a first electrode, a second electrode, anorganic layer between the first electrode and the second electrode, theorganic layer including an emission layer; and

an electron transport region between the emission layer and the secondelectrode;

where the emission layer includes a first compound represented byFormula 1 and a second compound represented by any one of Formulae 2-1to 2-5; and

the electron transport region includes a third compound represented byFormula 7:

In Formulae 1, 2-1 to 2-5, and 7,

A₁₁, A₁₂, A₁₃, A₁₄, A₂₁, and A₂₂ may be each independently selected froma benzene, a naphthalene, a pyridine, a pyrimidine, a quinoline, anisoquinoline, a 2,6-naphthyridine, a 1,8-naphthyridine, a1,5-naphthyridine, a 1,6-naphthyridine, a 1,7-naphthyridine, a2,7-naphthyridine, a quinoxaline, a phthalazine, a quinazoline, and acinnoline;

X₁₁ may be selected from O, S, N[(L₁₂)_(a12)-(R₁₂)_(b12)],C[(L₁₂)_(a12)-(R₁₂)_(b12)][R₁₇], Si[(L₁₂)_(a12)-(R₁₂)_(b12)][R₁₇],P[(L₁₂)_(a12)-(R₁₂)_(b12)], B[(L₁₂)_(a12)-(R₁₂)_(b12)], andP(═O)[(L₁₂)_(a12)-(R₁₂)_(b12)];

X₂₁ may be selected from O, S, N[(L₂₂)_(a22)-(R₂₂)_(b22)],C[(L₂₂)_(a22)-(R₂₂)_(b22)][R₂₆], Si[(L₂₂)_(a22)-(R₂₂)_(b22)][R₂₆],P[(L₂₂)_(a22)-(R₂₂)_(b22)], B[(L₂₂)_(a22)-(R₂₂)_(b22)], andP(═O)[(L₂₂)_(a22)-(R₂₂)_(b22)];

L₁₁ to L₁₃, L₂₁, L₂₂, and L₇₁ may be each independently selected from asubstituted or unsubstituted C₃-C₁₀ cycloalkylene group, a substitutedor unsubstituted C₁-C₁₀ heterocycloalkylene group, a substituted orunsubstituted C₃-C₁₀ cycloalkenylene group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenylene group, a substituted orunsubstituted C₆-C₆₀ arylene group, a substituted or unsubstitutedC₁-C₆₀ heteroarylene group, a substituted or unsubstituted divalentnon-aromatic condensed polycyclic group, and a substituted orunsubstituted divalent non-aromatic condensed heteropolycyclic group;

a11 to a13, a21, a22, and a71 may be each independently selected from 0,1, 2, 3, 4, and 5;

R₁₁ and R₁₂ may be each independently selected from R_(HT) and R_(ET),provided that at least one selected from R₁₁ and R₁₂ is R_(ET);

R₂₁ and R₂₂ may be each independently R_(HT);

R₇₁ may be R_(ET);

b11, b12, b21, and b22 may be each independently selected from 1, 2, 3,and 4;

R₁₃ to R₁₇, R₂₃ to R₂₆, and R₇₂ to R₈₀ may be each independentlyselected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid (herein, alsoreferring to a “carboxylic acid group”) or a salt thereof, a sulfonicacid (herein, also referring to a “sulfonic acid group”) or a saltthereof, a phosphoric acid (herein, also referring to a “phosphoric acidgroup”) or a salt thereof, a substituted or unsubstituted C₁-C₆₀ alkylgroup, a substituted or unsubstituted C₂-C₆₀ alkenyl group, asubstituted or unsubstituted C₂-C₆₀ alkynyl group, a substituted orunsubstituted C₁-C₆₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀cycloalkyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkylgroup, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, asubstituted or unsubstituted C₆-C₆₀ aryl group, a substituted orunsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstitutedC₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroarylgroup, a substituted or unsubstituted monovalent non-aromatic condensedpolycyclic group, a substituted or unsubstituted monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₁)(Q₂), —Si(Q₃)(Q₄)(Q₅), and—B(Q₆)(Q₇);

b13 to b16 and b23 to b25 may be each independently selected from 1, 2,3 and 4;

R_(HT) is a hole transport group;

R_(ET) is an electron transport group; and

at least one substituent of the substituted C₃-C₁₀ cycloalkylene group,the substituted C₁-C₁₀ heterocycloalkylene group, the substituted C₃-C₁₀cycloalkenylene group, the substituted C₁-C₁₀ heterocycloalkenylenegroup, the substituted C₆-C₆₀ arylene group, the substituted C₁-C₆₀heteroarylene group, the substituted divalent non-aromatic condensedpolycyclic group, the substituted divalent non-aromatic condensedheteropolycyclic group, the substituted C₁-C₆₀ alkyl group, thesubstituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀ alkynyl group,the substituted C₁-C₆₀ alkoxy group, the substituted C₃-C₁₀ cycloalkylgroup, the substituted C₁-C₁₀ heterocycloalkyl group, the substitutedC₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀ heterocycloalkenylgroup, the substituted C₆-C₆₀ aryl group, the substituted C₆-C₆₀ aryloxygroup, the substituted C₆-C₆₀ arylthio group, the substituted C₁-C₆₀heteroaryl group, the substituted monovalent non-aromatic condensedpolycyclic group, and the substituted monovalent non-aromatic condensedheteropolycyclic group may be selected from:

deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid group or a salt thereof, a sulfonic acid groupor a salt thereof, a phosphoric acid group or a salt thereof, a C₁-C₆₀alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and aC₁-C₆₀ alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid ora salt thereof, a phosphoric acid or a salt thereof, a C₃-C₁₀ cycloalkylgroup, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, aC₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxygroup, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₁₁)(Q₁₂), —Si(Q₁₃)(Q₁₄)(Q₁₅), and—B(Q₁₆)(Q₁₇);

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, aC₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group,a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₂₁)(Q₂₂), —Si(Q₂₃)(Q₂₄)(Q₂₅), and—B(Q₂₆)(Q₂₇); and

—N(Q₃₁)(Q₃₂), —Si(Q₃₃)(Q₃₄)(Q₃₅), and —B(Q₃₆)(Q₃₇);

where Q₁ to Q₇, Q₁₁ to Q₁₇, Q₂₁ to Q₂₇ and Q₃₁ to Q₃₇ may be eachindependently selected from hydrogen, a C₁-C₆₀ alkyl group, a C₁-C₆₀alkoxy group, a C₆-C₆₀ aryl group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, and a monovalentnon-aromatic condensed heteropolycyclic group.

In one or more embodiments of the present invention, an organiclight-emitting device includes a first electrode, a second electrode,and an organic layer between the first electrode and the secondelectrode and including an emission layer;

an electron transport region between the emission layer and the secondelectrode;

where the emission layer includes a first compound represented byFormula 1 and a second compound represented by any one of Formulae 2-1to 2-5; and

the electron transport region includes a third compound represented byFormula 7:

In Formulae 1, 2-1 to 2-5, and 7:

A₁₁, A₁₂, A₁₃, A₁₄, A₂₁, and A₂₂ may be each independently selected froma benzene, a naphthalene, a pyridine, a pyrimidine, a quinoline, anisoquinoline, a 2,6-naphthyridine, a 1,8-naphthyridine, a1,5-naphthyridine, a 1,6-naphthyridine, a 1,7-naphthyridine, a2,7-naphthyridine, a quinoxaline, a phthalazine, a quinazoline, and acinnoline;

X₁₁ may be selected from O, S, N[(L₁₂)_(a12)-(R₁₂)_(b12)],C[(L₁₂)_(a12)-(R₁₂)_(b12)][R₁₇], Si[(L₁₂)_(a12)-(R₁₂)_(b12)][R₁₇],P[(L₁₂)_(a12)-(R₁₂)_(b12)], B[(L₁₂)_(a12)-(R₁₂)_(b12)], andP(═O)[(L₁₂)_(a12)-(R₁₂)_(b12)];

X₂₁ may be selected from O, S, N[(L₂₂)_(a22)-(R₂₂)_(b22)],C[(L₂₂)_(a22)-(R₂₂)_(b22)][R₂₆], Si[(L₂₂)_(a22)-(R₂₂)_(b22)][R₂₆],P[(L₂₂)_(a22)-(R₂₂)_(b22)], B[(L₂₂)_(a22)-(R₂₂)_(b22)], andP(═O)[(L₂₂)_(a22)-(R₂₂)_(b22)];

L₁₁ to L₁₃, L₂₁, L₂₂, and L₇₁ may be each independently selected from asubstituted or unsubstituted C₃-C₁₀ cycloalkylene group, a substitutedor unsubstituted C₁-C₁₀ heterocycloalkylene group, a substituted orunsubstituted C₃-C₁₀ cycloalkenylene group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenylene group, a substituted orunsubstituted C₆-C₆₀ arylene group, a substituted or unsubstitutedC₁-C₆₀ heteroarylene group, a substituted or unsubstituted divalentnon-aromatic condensed polycyclic group, and a substituted orunsubstituted divalent non-aromatic condensed heteropolycyclic group;

a11 to a13, a21, a22, and a71 may be each independently selected from 0,1, 2, 3, 4, and 5;

R₁₁ and R₁₂ may be each independently R_(HT);

R₂₁ and R₂₂ may be each independently selected from R_(HT) and R_(ET),provided that at least one selected from R₂₁ and R₂₂ is R_(ET);

R₇₁ may be R_(ET);

b11, b12, b21, and b22 may be each independently selected from 1, 2, 3,and 4;

R₁₃ to R₁₇, R₂₃ to R₂₆, and R₇₂ to R₈₀ may be each independentlyselected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a substituted or unsubstituted C₁-C₆₀ alkyl group, a substituted orunsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstitutedC₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxygroup, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted a monovalent non-aromatic condensed polycyclic group, anda substituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group;

b13 to b16 and b23 to b25 may be each independently selected from 1, 2,3 and 4;

R_(HT) is a hole transport group;

R_(ET) is an electron transport group; and

at least one substituent of the substituted C₃-C₁₀ cycloalkylene group,the substituted C₁-C₁₀ heterocycloalkylene group, the substituted C₃-C₁₀cycloalkenylene group, the substituted C₁-C₁₀ heterocycloalkenylenegroup, the substituted C₆-C₆₀ arylene group, the substituted C₁-C₆₀heteroarylene group, the substituted divalent non-aromatic condensedpolycyclic group, the substituted divalent non-aromatic condensedheteropolycyclic group, the substituted C₁-C₆₀ alkyl group, thesubstituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀ alkynyl group,the substituted C₁-C₆₀ alkoxy group, the substituted C₃-C₁₀ cycloalkylgroup, the substituted C₁-C₁₀ heterocycloalkyl group, the substitutedC₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀ heterocycloalkenylgroup, the substituted C₆-C₆₀ aryl group, the substituted C₆-C₆₀ aryloxygroup, the substituted C₆-C₆₀ arylthio group, the substituted C₁-C₆₀heteroaryl group, the substituted monovalent non-aromatic condensedpolycyclic group, and the substituted monovalent non-aromatic condensedheteropolycyclic group may be selected from:

deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid group or a salt thereof, a sulfonic acid groupor a salt thereof, a phosphoric acid group or a salt thereof, a C₁-C₆₀alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and aC₁-C₆₀ alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid ora salt thereof, a phosphoric acid or a salt thereof, a C₃-C₁₀ cycloalkylgroup, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, aC₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxygroup, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₁₁)(Q₁₂), —Si(Q₁₃)(Q₁₄)(Q₁₅), and—B(Q₁₆)(Q₁₇);

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, aC₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group,a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₂₁)(Q₂₂), —Si(Q₂₃)(Q₂₄)(Q₂₅), and—B(Q₂₆)(Q₂₇); and

—N(Q₃₁)(Q₃₂), —Si(Q₃₃)(Q₃₄)(Q₃₅), and —B(Q₃₆)(Q₃₇);

where Q₁₁ to Q₁₇, Q₂₁ to Q₂₇, and Q₃₁ to Q₃₇ may be each independentlyselected from hydrogen, a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkoxy group, aC₆-C₆₀ aryl group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromaticcondensed polycyclic group, and a monovalent non-aromatic condensedheteropolycyclic group.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects will become apparent and more readilyappreciated from the following description of the embodiments, taken inconjunction with the drawing, which is a schematic cross-sectional viewof an organic light-emitting device according to one or more embodimentsof the present invention.

DETAILED DESCRIPTION

Reference will now be made in more detail to embodiments, examples ofwhich are illustrated in the accompanying drawing, wherein likereference numerals refer to the like elements throughout. In thisregard, the present embodiments may have different forms and should notbe construed as being limited to the descriptions set forth herein.Accordingly, the embodiments are merely described below, by referring tothe drawing, to explain aspects of the present description.

The present disclosure may be embodied in many different forms andshould not be construed as being limited to the embodiments set forthherein; rather, these embodiments are provided so that this disclosuremay be understood by those skilled in the art.

As used herein, the singular forms “a,” “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise.

It will be further understood that the terms “comprises” and/or“comprising” used herein specify the presence of stated features orcomponents, but do not preclude the presence or addition of one or moreother features or components.

It will be understood that when a layer, region, or component isreferred to as being “on” or “onto” another layer, region, or component,it may be directly or indirectly formed on the other layer, region, orcomponent. That is, for example, intervening layers, regions, orcomponents may be present.

Sizes of components in the drawing may be exaggerated for convenience ofexplanation. In other words, since sizes and thicknesses of componentsin the drawing are arbitrarily illustrated for convenience ofexplanation, the following embodiments are not limited thereto.

The expression “(an organic layer) includes a first compound” usedherein may be interpreted as a case in which “(an organic layer)includes one or more identical first compounds represented by Formula 1or two or more different first compounds represented by Formula 1.”

The term “organic layer” used herein refers to a single layer and/or aplurality of layers between the first electrode and the second electrodeof the organic light-emitting device. A material included in the“organic layer” is not limited to an organic material.

Expressions such as “at least one of” and “one of,” when preceding alist of elements, modify the entire list of elements and do not modifythe individual elements of the list. Further, the use of “may” whendescribing embodiments of the present invention refers to “one or moreembodiments of the present invention.”

In addition, as used herein, the terms “use,” “using,” and “used” may beconsidered synonymous with the terms “utilize,” “utilizing,” and“utilized,” respectively. Also, the term “exemplary” is intended torefer to an example or illustration.

As used herein, the term “substantially,” “about,” and similar terms areused as terms of approximation and not as terms of degree, and areintended to account for the inherent deviations in measured orcalculated values that would be recognized by those of ordinary skill inthe art.

Also, any numerical range recited herein is intended to include allsubranges of the same numerical precision subsumed within the recitedrange. For example, a range of “1.0 to 10.0” is intended to include allsubranges between (and including) the recited minimum value of 1.0 andthe recited maximum value of 10.0, that is, having a minimum value equalto or greater than 1.0 and a maximum value equal to or less than 10.0,such as, for example, 2.4 to 7.6. Any maximum numerical limitationrecited herein is intended to include all lower numerical limitationssubsumed therein and any minimum numerical limitation recited in thisspecification is intended to include all higher numerical limitationssubsumed therein. Accordingly, Applicant reserves the right to amendthis specification, including the claims, to expressly recite anysub-range subsumed within the ranges expressly recited herein. All suchranges are intended to be inherently described in this specificationsuch that amending to expressly recite any such subranges would complywith the requirements of 35 U.S.C. § 1 12, first paragraph, and 35U.S.C. § 132(a).

The drawing is a schematic cross-sectional view of an organiclight-emitting device 10 according to one or more embodiments of thepresent invention.

In the drawing, a substrate may be additionally positioned under thefirst electrode 110 or above the second electrode 190. The substrate maybe a glass substrate or transparent plastic substrate, each withexcellent mechanical strength, thermal stability, transparency, surfacesmoothness, ease of handling, and/or water-resistance.

The first electrode 110 may be formed by depositing or sputtering amaterial for forming the first electrode on the substrate. When thefirst electrode 110 is an anode, the material for the first electrode110 may be selected from materials with a high work function so asfacilitate hole injection. The first electrode 110 may be a reflectiveelectrode or a transmissive electrode. The material for the firstelectrode 110 may be a transparent and highly conductive material, andnon-limiting examples of such a material include indium tin oxide (ITO),indium zinc oxide (IZO), tin oxide (SnO₂), and zinc oxide (ZnO). Whenthe first electrode 110 is a semi-transmissive electrode or a reflectiveelectrode, as a material for forming the first electrode, at least oneof magnesium (Mg), aluminum (Al), aluminum-lithium (Al—Li), calcium(Ca), magnesium-indium (Mg—In), and magnesium-silver (Mg—Ag) may beused.

The first electrode 110 may have a single-layer structure, or amulti-layer structure including two or more layers. For example, thefirst electrode 110 may have a three-layered structure of ITO/Ag/ITO,but the structure of the first electrode 110 is not limited thereto.

An organic layer 150 including an emission layer may be positioned onthe first electrode 110. The organic layer 150 may include a holetransport region between the first electrode 110 and the emission layerand an electron transport region between the emission layer and thesecond electrode 190.

The hole transport region may include at least one selected from a holeinjection layer (HIL), a hole transport layer (HTL), a buffer layer, andan electron blocking layer (EBL), and the electron transport region mayinclude at least one selected from a hole blocking layer (HBL), anelectron transport layer (ETL), and an electron injection layer (EIL),but they are not limited thereto.

The hole transport region may have a single-layered structure formed ofa single material, a single-layered structure formed of a plurality ofdifferent materials, or a multi-layered structure having a plurality oflayers formed of a plurality of different materials.

For example, the hole transport region may have a single-layeredstructure formed of a plurality of different materials, or a structureof hole injection layer/hole transport layer, a structure of holeinjection layer/hole transport layer/buffer layer, a structure of holeinjection layer/buffer layer, a structure of hole transport layer/bufferlayer, a structure of hole injection layer/hole transport layer/electronblocking layer, or a structure of a hole transport layer/electronblocking layer, wherein the layers of each structure are sequentiallystacked on the first electrode 110 in the stated order, but embodimentsof the present invention are not limited thereto.

When the hole transport region includes a hole injection layer, the holeinjection layer may be formed on the first electrode 110 by using(utilizing) one or more suitable methods, such as vacuum deposition,spin coating casting, a Langmuir-Blodgett (LB) method, ink-jet printing,laser-printing, and/or laser-induced thermal imaging.

When the hole injection layer is formed by vacuum deposition, forexample, the vacuum deposition may be performed at a depositiontemperature of about 100 to about 500° C., at a vacuum degree of about10⁻⁸ to about 10⁻³ torr, and at a deposition rate of about 0.01 to about100 Å/sec, depending on the compound for forming the hole injectionlayer to be deposited, and the structure of the hole injection layer tobe formed.

When the hole injection layer is formed by spin coating, the spincoating may be performed at a coating rate of about 2000 rpm to about5000 rpm, and at a temperature of about 80° C. to about 200° C.,depending on the compound for forming the hole injection layer to bedeposited, and the structure of the hole injection layer to be formed.

When the hole transport region includes a hole transport layer, the holetransport layer may be formed on the first electrode 110 or the holeinjection layer by using one or more suitable methods, such as vacuumdeposition, spin coating, casting, a LB method, ink-jet printing,laser-printing, and/or laser-induced thermal imaging. When the holetransport layer is formed by vacuum deposition and/or spin coating,deposition and coating conditions for the hole transport layer may bethe same as (or similar to) the deposition and coating conditions forthe hole injection layer.

The hole transport region may include at least one selected fromm-MTDATA, TDATA, 2-TNATA, NPB, 3-NPB, TPD, Spiro-TPD, Spiro-NPB,methylated-NPB, TAPC, HMTPD, 4,4′,4″-tris(N-carbazolyl)triphenylamine(TCTA), polyaniline/dodecylbenzenesulfonic acid (Pani/DBSA),poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (PEDOT/PSS),polyaniline/camphor sulfonicacid (Pani/CSA),(polyaniline)/poly(4-styrenesulfonate) (PANI/PSS), a compoundrepresented by Formula 201 below, and a compound represented by Formula202 below:

In Formulae 201 and 202,

descriptions of L₂₀₁ to L₂₀₅ may be the same as those provided herein inconnection with L₁₁;

xa1 to xa4 may be each independently selected from 0, 1, 2, and 3;

xa5 may be selected from 1, 2, 3, 4, and 5; and

R₂₀₁ to R₂₀₄ may be each independently understood by referring to thedescription provided herein in connection with R₁₁.

In some embodiments, in Formulae 201 and 202,

L₂₀₁ to L₂₀₅ may be each independently selected from a phenylene group,a naphthylene group, a fluorenylene group, a spiro-fluorenylene group, abenzofluorenylene group, a dibenzofluorenylene group, a phenanthrenylenegroup, an anthracenylene group, a pyrenylene group, a chrysenylenegroup, a pyridinylene group, a pyrazinylene group, a pyrimidinylenegroup, a pyridazinylene group, a quinolinylene group, anisoquinolinylene group, a quinoxalinylene group, a quinazolinylenegroup, a carbazolylene group, and a triazinylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-fluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a pyrenylene group, a chrysenylene group, a pyridinylene group, apyrazinylene group, a pyrimidinylene group, a pyridazinylene group, aquinolinylene group, an isoquinolinylene group, a quinoxalinylene group,a quinazolinylene group, a carbazolylene group, and a triazinylenegroup, each substituted with at least one selected from deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an aminogroup, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, aphosphoric acid or a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxygroup, a phenyl group, a naphthyl group, a fluorenyl group, aspiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group,a phenanthrenyl group, an anthracenyl group, a pyrenyl group, achrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, an isoindolyl group, a quinolinyl group, anisoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, acarbazolyl group, and a triazinyl group;

xa1 to xa4 may be each independently 0, 1, or 2;

xa5 may be 1, 2, or 3;

R₂₀₁ to R₂₀₄ may be each independently selected from:

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, a chrysenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group,a quinazolinyl group, a carbazolyl group, and a triazinyl group; and

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, a chrysenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group,a quinazolinyl group, a carbazolyl group, and a triazinyl group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenylgroup, a naphthyl group, an azulenyl group, a fluorenyl group, aspiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group,a phenanthrenyl group, an anthracenyl group, a pyrenyl group, achrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group,a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and atriazinyl group, but they are not limited thereto.

The compound represented by Formula 201 may be represented by Formula201A:

For example, the compound represented by Formula 201 may be representedby Formula 201A-1 below, but is not limited thereto:

For example, the compound represented by Formula 202 may be representedby Formula 202A below, but is not limited thereto:

L₂₀₁ to L₂₀₃, xa1 to xa3, xa5, and R₂₀₂ to R₂₀₄ in Formulae 201A, 201A-1and 202A are as described above, and R₂₁₁ and R₂₁₂ may be eachindependently understood by referring to the description provided hereinin connection with R₂₀₃, and R₂₁₃ to R₂₁₆ may be each independentlyselected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, aC₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, and a monovalent non-aromaticcondensed heteropolycyclic group.

For example, in Formulae 201A, 201A-1, and 202A,

L₂₀₁ to L₂₀₃ may be each independently selected from:

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-fluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a pyrenylene group, a chrysenylene group, a pyridinylene group, apyrazinylene group, a pyrimidinylene group, a pyridazinylene group, aquinolinylene group, an isoquinolinylene group, a quinoxalinylene group,a quinazolinylene group, a carbazolylene group, and a triazinylenegroup; and

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-fluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a pyrenylene group, a chrysenylene group, a pyridinylene group, apyrazinylene group, a pyrimidinylene group, a pyridazinylene group, aquinolinylene group, an isoquinolinylene group, a quinoxalinylene group,a quinazolinylene group, a carbazolylene group, and a triazinylenegroup, each substituted with at least one selected from deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an aminogroup, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, aphosphoric acid or a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxygroup, a phenyl group, a naphthyl group, a fluorenyl group, aspiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group,a phenanthrenyl group, an anthracenyl group, a pyrenyl group, achrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group,a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and atriazinyl group;

xa1 to xa3 may be each independently 0 or 1;

R₂₀₂ to R₂₀₄, R₂₁₁, and R₂₁₂ may be each independently selected from:

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, a chrysenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group,a quinazolinyl group, a carbazolyl group, and a triazinyl group; and

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, a chrysenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group,a quinazolinyl group, a carbazolyl group, and a triazinyl group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenylgroup, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group,an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinylgroup, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, aquinolinyl group, an isoquinolinyl group, a quinoxalinyl group, aquinazolinyl group, a carbazolyl group, and a triazinyl group;

R₂₁₃ and R₂₁₄ may be each independently selected from:

a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group;

a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, each substituted with atleast one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, a chrysenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group,a quinazolinyl group, a carbazolyl group, and a triazinyl group;

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, a chrysenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group,a quinazolinyl group, a carbazolyl group, and a triazinyl group; and

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, a chrysenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group,a quinazolinyl group, a carbazolyl group, and a triazinyl group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenylgroup, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group,an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinylgroup, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, aquinolinyl group, an isoquinolinyl group, a quinoxalinyl group, aquinazolinyl group, a carbazolyl group, and a triazinyl group; and

R₂₁₅ and R₂₁₆ may be each independently selected from:

hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid ora salt thereof, a phosphoric acid or a salt thereof, a C₁-C₂₀ alkylgroup, and a C₁-C₂₀ alkoxy group;

a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, each substituted with atleast one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, a chrysenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group,a quinazolinyl group, a carbazolyl group, and a triazinyl group;

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, a chrysenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group,a quinazolinyl group, and a triazinyl group; and

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, a chrysenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group,a quinazolinyl group, a carbazolyl group, and a triazinyl group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenylgroup, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group,an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinylgroup, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, aquinolinyl group, an isoquinolinyl group, a quinoxalinyl group, aquinazolinyl group, a carbazolyl group, and a triazinyl group; and

xa5 may be 1 or 2.

R₂₁₃ and R₂₁₄ in Formulae 201A, and 201A-1 may bind to each other toform a saturated or unsaturated ring.

The compound represented by Formula 201, and the compound represented byFormula 202 may each independently include compounds HT1 to HT20illustrated below, but are not limited thereto.

A thickness of the hole transport region may be in a range of about 100Å to about 10,000 Å, for example, about 100 Å to about 1,000 Å. When thehole transport region includes both a hole injection layer and a holetransport layer, a thickness of the hole injection layer may be in arange of about 100 Å to about 10,000 Å, for example, about 100 Å toabout 9,950 Å, or about 100 Å to about 1,000 Å, and a thickness of thehole transport layer may be in a range of about 50A to about 2,000 Å,for example about 100 Å to about 1,500 Å. When the thicknesses of thehole transport region, the hole injection layer, and the hole transportlayer are within any of these ranges, satisfactory hole transportingcharacteristics may be obtained without a substantial increase indriving voltage.

The hole transport region may further include, in addition to thesematerials, a charge-generation material for the improvement ofconductive properties. The charge-generation material may behomogeneously or unhomogeneously dispersed in the hole transport region.

The charge-generation material may be, for example, a p-dopant. Thep-dopant may be selected from a quinone derivative, a metal oxide, and acyano group-containing compound, but embodiments of the presentinvention are not limited thereto. Non-limiting examples of the p-dopantinclude quinone derivatives, such as tetracyanoquinonedimethane (TCNQ)and/or 2,3,5,6-tetrafluoro-tetracyano-1,4-benzoquinonedimethane(F4-TCNQ); metal oxides, such as tungsten oxide and/or molybdenum oxide,and Compound HT-D1 illustrated below.

The hole transport region may further include, in addition to the holeinjection layer and the hole transport layer, at least one of a bufferlayer and an electron blocking layer. Since the buffer layer maycompensate for an optical resonance distance according to a wavelengthof light emitted from the emission layer, light-emission efficiency ofthe formed organic light-emitting device may be improved. For use as amaterial included in the buffer layer, materials that are included inthe hole transport region may be used. The electron blocking layerprevents or substantially blocks the injection of electrons from theelectron transport region.

In some embodiments, an emission layer is formed on the first electrode110 or the hole transport region by using (utilizing) one or moresuitable methods, such as vacuum deposition, spin coating, casting, a LBmethod, ink-jet printing, laser-printing, and/or laser-induced thermalimaging. When the emission layer is formed by vacuum deposition and/orspin coating, deposition and coating conditions for the emission may bethe same as (or similar to) those for the hole injection layer.

When the organic light-emitting device 10 is a full color organiclight-emitting device, the emission layer may be patterned into a redemission layer, a green emission layer, and/or a blue emission layer,according to a sub pixel. In some embodiments, the emission layer mayhave a stacked structure of a red emission layer, a green emissionlayer, and a blue emission layer, or may include a red-light emissionmaterial, a green-light emission material, and a blue-light emissionmaterial, which are mixed with each other in a single layer, to emitwhite light. In some embodiments, the emission layer may be a whiteemission layer, and may further include a color converting layer or acolor filter to turn white light into light of a desired color.

The emission layer may include a host and a dopant.

In some embodiments, the host may include a first compound representedby Formula 1 and a second compound represented by one of Formulae 2-1 to2-5;

A₁₁, A₁₂, A₁₃, A₁₄, A₂₁, and A₂₂ in Formulae 1, and 2-1 to 2-5 may beeach independently selected from a benzene, a naphthalene, a pyridine, apyrimidine, a quinoline, an isoquinoline, a 2,6-naphthyridine, a1,8-naphthyridine, a 1,5-naphthyridine, a 1,6-naphthyridine, a1,7-naphthyridine, a 2,7-naphthyridine, a quinoxaline, a phthalazine, aquinazoline, and a cinnoline.

For example, A₁₁, A₁₂, A₁₃, A₁₄, A₂₁, and A₂₂ in Formulae 1, and 2-1 to2-5 may be each independently selected from a benzene, a naphthalene, apyridine, a pyrimidine, a quinoline, an isoquinoline, a2,6-naphthyridine, a 1,8-naphthyridine, a 1,5-naphthyridine, a1,6-naphthyridine, a 1,7-naphthyridine, a 2,7-naphthyridine, aquinoxaline, and a quinazoline.

In some embodiments, in Formula 1, A₁₁ and A₁₄ may be each independentlyselected from a benzene, a naphthalene, a pyridine, a pyrimidine, aquinoline, an isoquinoline, a 2,6-naphthyridine, a 1,8-naphthyridine, a1,5-naphthyridine, a 1,6-naphthyridine, a 1,7-naphthyridine, a2,7-naphthyridine, a quinoxaline, and a quinazoline, and A₁₂ and A₁₃ mayeach independently be a benzene, but they are not limited thereto.

In some embodiments, in Formula 1, A₁₁ and A₁₄ may be each independentlyselected from a benzene and a naphthalene, and A₁₂ and A₁₃ may be eachindependently a benzene, but they are not limited thereto.

In some embodiments, A₁₁ to A₁₄ in Formula 1 may be each independently abenzene, but they are not limited thereto.

In some embodiments, A₂₁ and A₂₂ in Formulae 2-1 to 2-5 may be eachindependently a benzene, but they are not limited thereto.

X₁₁ in Formula 1 may be selected from O, S, N[(L₁₂)_(a12)-(R₁₂)_(b12)],C[(L₁₂)_(a12)-(R₁₂)_(b12)][R₁₇], Si[(L₁₂)_(a12)-(R₁₂)_(b12)][R₁₇],P[(L₁₂)_(a12)-(R₁₂)_(b12)], B[(L₁₂)_(a12)-(R₁₂)_(b12)], andP(═O)[(L₁₂)_(a12)-(R₁₂)_(b12)].

For example, X₁₁ in Formula 1 may be selected from O, S,N[(L₁₂)_(a12)-(R₁₂)_(b12)], C[(L₁₂)_(a12)-(R₁₂)_(b12)][R₁₇],Si[(L₁₂)_(a2)-(R₁₂)_(b2)][R₁₇], P[(L₁₂)_(a12)-(R₁₂)_(b12)],B[(L₁₂)_(a12)-(R₁₂)_(b12)], and P(═O)[(L₁₂)_(a12)-(R₁₂)_(b12)]; and R₁₂and R₁₇ may be optionally connected to each other to form a saturated orunsaturated ring, but they are not limited thereto.

In some embodiments, X₁₁ in Formula 1 may be selected from O, S,N[(L₁₂)_(a12)-(R₁₂)_(b12)], and C[(L₁₂)_(a12)-(R₁₂)_(b12)][R₁₇], but isnot limited thereto.

X₂₁ in Formulae 2-1 to 2-5 may be selected from O, S,N[(L₂₂)_(a22)-(R₂₂)_(b22)], C[(L₂₂)_(a22)-(R₂₂)_(b22)][R₂₆],Si[(L₂₂)_(a22)-(R₂₂)_(b22)][R₂₆], P[(L₂₂)_(a22)-(R₂₂)_(b22)],B[(L₂₂)_(a22)-(R₂₂)_(b22)], and P(═O)[(L₂₂)_(a22)-(R₂₂)_(b22)].

For example, X₂₁ in Formulae 2-1 to 2-5 may be selected from O, S,N[(L₂₂)_(a22)-(R₂₂)_(b22)] and C[(L₂₂)_(a22)-(R₂₂)_(b22)][R₂₆], but isnot limited thereto.

L₁₁ to L₁₃, L₂₁, and L₂₂ in Formulae 1 and 2-1 to 2-5 may be eachindependently selected from a substituted or unsubstituted C₃-C₁₀cycloalkylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group; and

at least one substituent of the substituted C₃-C₁₀ cycloalkylene group,the substituted C₁-C₁₀ heterocycloalkylene group, the substituted C₃-C₁₀cycloalkenylene group, the substituted C₁-C₁₀ heterocycloalkenylenegroup, the substituted C₆-C₆₀ arylene group, the substituted C₁-C₆₀heteroarylene group, the substituted divalent non-aromatic condensedpolycyclic group, and the substituted divalent non-aromatic condensedheteropolycyclic group may be selected from:

deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid group or a salt thereof, a sulfonic acid groupor a salt thereof, a phosphoric acid group or a salt thereof, a C₁-C₆₀alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and aC₁-C₆₀ alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid ora salt thereof, a phosphoric acid or a salt thereof, a C₃-C₁₀ cycloalkylgroup, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, aC₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxygroup, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₁₁)(Q₁₂), —Si(Q₁₃)(Q₁₄)(Q₁₅), and—B(Q₁₆)(Q₁₇);

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, aC₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group,a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₂₁)(Q₂₂), —Si(Q₂₃)(Q₂₄)(Q₂₅), and—B(Q₂₆)(Q₂₇); and

—N(Q₃₁)(Q₃₂), —Si(Q₃₃)(Q₃₄)(Q₃₅), and —B(Q₃₆)(Q₃₇);

where Q₁₁ to Q₁₇, Q₂₁ to Q₂₇, and Q₃₁ to Q₃₇ may be each independentlyselected from hydrogen, a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkoxy group, aC₆-C₆₀ aryl group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromaticcondensed polycyclic group, and a monovalent non-aromatic condensedheteropolycyclic group.

For example, L₁₁ to L₁₃, L₂₁, and L₂₂ in Formulae 1 and 2-1 to 2-5 maybe each independently selected from a phenylene group, a naphthylenegroup, a fluorenylene group, a phenanthrenylene group, a anthracenylenegroup, a triphenylenylene group, a pyrenylene group, a chrysenylenegroup, a pyrrolylene group, a thiophenylene group, a furanylene group,an imidazolylene group, a pyridinylene group, a pyrazinylene group, apyrimidinylene group, a pyridazinylene group, an indolylene group, aquinolinylene group, an isoquinolinylene group, a benzoquinolinylenegroup, a phenanthridinylene group, an acridinylene group, aphenanthrolinylene group, a benzofuranylene group, a benzothiophenylenegroup, a triazolylene group, a tetrazolylene group, a triazinylenegroup, a dibenzofuranylene group, and a dibenzothiophenylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, aphenanthrenylene group, an anthracenylene group, a triphenylenylenegroup, a pyrenylene group, a chrysenylene group, a pyrrolylene group, athiophenylene group, a furanylene group, an imidazolylene group, apyridinylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, an indolylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phenanthridinylenegroup, an acridinylene group, a phenanthrolinylene group, abenzofuranylene group, a benzothiophenylene group, a triazolylene group,a tetrazolylene group, a triazinylene group, a dibenzofuranylene group,and a dibenzothiophenylene group, each substituted with at least oneselected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid or a salt thereof, asulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, aC₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a naphthylgroup, a fluorenyl group, a spiro-fluorenyl group, a phenalenyl group, aphenanthrenyl group, an anthracenyl group, a fluoranthenyl group, atriphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenylgroup, a pentaphenyl group, a hexacenyl group, a pentacenyl group, apyrrolyl group, a thiophenyl group, a furanyl group, an imidazolylgroup, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, anoxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinylgroup, a pyrimidinyl group, a pyridazinyl group, an indolyl group, anindazolyl group, a quinolinyl group, an isoquinolinyl group, acarbazolyl group, a benzoquinolinyl group, a phthalazinyl group, anaphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a benzimidazolyl group, a benzofuranyl group, abenzothiophenyl group, a benzoxazolyl group, a triazolyl group, atetrazolyl group, an oxadiazolyl group, a triazinyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl groupand a dibenzocarbazolyl group, but they are not limited thereto.

In some embodiments, L₁₁ to L₁₃, L₂₁, and L₂₂ in Formulae 1 and 2-1 to2-5 may be each independently selected from a phenylene group, anaphthylene group, a fluorenylene group, a dibenzofuranylene group, anda dibenzothiophenylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, adibenzofuranylene group, and a dibenzothiophenylene group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a cyano group, a nitro group, a C₁-C₂₀ alkyl group, a phenyl group, anda naphthyl group, but they are not limited thereto.

In some embodiments, L₁₁ to L₁₃, L₂₁, and L₂₂ in Formulae 1 and 2-1 to2-5 may be each independently selected from groups represented byFormulae 3-1 to 3-19, but they are not limited thereto:

In Formulae 3-1 to 3-19,

X₃₁ may be selected from O, S, and C(R₃₃)(R₃₄);

R₃₁ to R₃₄ may be each independently selected from hydrogen, deuterium,—F, —Cl, —Br, —I, a cyano group, a nitro group, a methyl group, an ethylgroup, an n-propyl group, an iso-propyl group, an n-butyl group,iso-butyl group, a sec-butyl group, a tert-butyl group, a phenyl group,and a naphthyl group;

b31 may be selected from 1, 2, 3, and 4;

b32 may be selected from 1, 2, 3, 4, 5, and 6;

b33 may be selected from 1, 2, and 3; and

* and *′ each indicate a binding site to a neighboring atom.

In some embodiments, L₁₁ to L₁₃, L₂₁, and L₂₂ in Formulae 1 and 2-1 to2-5 may be each independently selected from groups represented byFormulae 4-1 to 4-13, but they are not limited thereto:

In Formulae 4-1 to 4-13,

* and *′ each indicate a binding site to a neighboring atom.

a11 in Formula 1 indicates the number of L₁₁, and a11 may be selectedfrom 0, 1, 2, 3, 4, and 5. When a11 is 0, -(L₁₁)_(a11)- indicates asingle bond. When a11 is 2 or more, a plurality of L₁₁ may be identicalto or different from each other. For example, a11 in Formula 1 may beselected from 0 and 1, but is not limited thereto.

a12 in Formula 1 indicates the number of L₁₂, and a12 may be selectedfrom 0, 1, 2, 3, 4, and 5. When a12 is 0, -(L₁₂)_(a12)- is a singlebond. When a12 is 2 or more, a plurality of L₁₂ may be identical to ordifferent from each other. For example, a12 in Formula 1 may be selectedfrom 0 and 1, but is not limited thereto.

a13 in Formula 1 indicates the number of L₁₃, and a13 may be selectedfrom 0, 1, 2, 3, 4, and 5. When a13 is 0, -(L₁₃)_(a13)- indicates asingle bond. When a13 is 2 or more, a plurality of L₁₃ may be identicalto or different from each other. For example, a13 in Formula 1 may beselected from 0 and 1, but is not limited thereto. In some embodiments,a13 in Formula 1 may be 0, but is not limited thereto.

a21 in Formulae 2-1 to 2-5 indicates the number of L₂₁, and a21 may beselected from 0, 1, 2, 3, 4, and 5. When a21 is 0, -(L₂₁)_(a21)-indicates a single bond. When a21 is 2 or more, a plurality of L₂₁ maybe identical to or different from each other. For example, a21 inFormula 1 may be selected from 0 and 1, but is not limited thereto.

a22 in Formulae 2-1 to 2-5 indicates the number of L₂₂, and a22 may beselected from 0, 1, 2, 3, 4, and 5. When a22 is 0, -(L₂₂)_(a22)- is asingle bond. When a22 is 2 or more, a plurality of L₂₂ may be identicalto or different from each other. For example, a22 in Formula 1 may beselected from 0 and 1, but is not limited thereto.

In Formulae 1 and 2-1 to 2-5, R₁₁ and R₁₂ may be each independentlyselected from R_(HT) and R_(ET), provided that at least one selectedfrom R₁₁ and R₁₂ is R_(ET); and R₂₁ and R₂₂ may be each independentlyR_(HT); where R_(HT) is a hole transport group and R_(ET) is an electrontransport group. R_(HT) and R_(ET) will be described in detail later.

b11 in Formula 1 indicates the number of R₁₁, and b11 may be selectedfrom 1, 2, 3, and 4. When b11 is 2 or more, a plurality of R₁₁ may beidentical to or different from each other.

b12 in Formula 1 indicates the number of R₁₂, and b12 may be selectedfrom 0, 1, 2, 3, and 4. When b12 is 2 or more, a plurality of R₁₂ may beidentical to or different from each other.

b21 in Formulae 2-1 to 2-5 indicates the number of R₂₁, and may beselected from 1, 2, 3, and 4. When b21 is 2 or more, a plurality of R₂₁may be identical to or different from each other.

b22 in Formulae 2-1 to 2-5 indicates the number of R₂₂, and may beselected from 1, 2, 3, and 4. When b22 is 2 or more, a plurality of R₂₂may be identical to or different from each other.

R₁₃ to R₁₇ and R₂₃ to R₂₆ in Formulae 1 and 2-1 to 2-5 may be eachindependently selected from hydrogen, deuterium, —F, —Cl, —Br, —I, ahydroxyl group, a cyano group, a nitro group, an amino group, an amidinogroup, a hydrazine group, a hydrazone group, a carboxylic acid or a saltthereof, a sulfonic acid or a salt thereof, a phosphoric acid or a saltthereof, a substituted or unsubstituted C₁-C₆₀ alkyl group, asubstituted or unsubstituted C₂-C₆₀ alkenyl group, a substituted orunsubstituted C₂-C₆₀ alkynyl group, a substituted or unsubstitutedC₁-C₆₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀ cycloalkylgroup, a substituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted monovalent non-aromatic condensed polycyclic group, asubstituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group, —N(Q₁)(Q₂), —Si(Q₃)(Q₄)(Q₅), and —B(Q₆)(Q₇);

at least one substituent of the substituted C₁-C₆₀ alkyl group, thesubstituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀ alkynyl group,the substituted C₁-C₆₀ alkoxy group, the substituted C₃-C₁₀ cycloalkylgroup, the substituted C₁-C₁₀ heterocycloalkyl group, the substitutedC₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀ heterocycloalkenylgroup, the substituted C₆-C₆₀ aryl group, the substituted C₆-C₆₀ aryloxygroup, the substituted C₆-C₆₀ arylthio group, the substituted C₁-C₆₀heteroaryl group, the substituted a monovalent non-aromatic condensedpolycyclic group, and the substituted monovalent non-aromatic condensedheteropolycyclic group may be selected from:

deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid group or a salt thereof, a sulfonic acid groupor a salt thereof, a phosphoric acid group or a salt thereof, a C₁-C₆₀alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and aC₁-C₆₀ alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid ora salt thereof, a phosphoric acid or a salt thereof, a C₃-C₁₀ cycloalkylgroup, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, aC₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxygroup, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₁₁)(Q₁₂), —Si(Q₁₃)(Q₁₄)(Q₁₅), and—B(Q₁₆)(Q₁₇);

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, aC₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group,a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₂₁)(Q₂₂), —Si(Q₂₃)(Q₂₄)(Q₂₅), and—B(Q₂₆)(Q₂₇); and

—N(Q₃₁)(Q₃₂), —Si(Q₃₃)(Q₃₄)(Q₃₅), and —B(Q₃₆)(Q₃₇);

where Q₁ to Q₇, Q₁₁ to Q₁₇, Q₂₁ to Q₂₇ and Q₃₁ to Q₃₇ may be eachindependently selected from hydrogen, a C₁-C₆₀ alkyl group, a C₁-C₆₀alkoxy group, a C₆-C₆₀ aryl group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, and a monovalentnon-aromatic condensed heteropolycyclic group.

For example, R₁₃ to R₁₇ and R₂₃ to R₂₆ in Formulae 1 and 2-1 to 2-5 maybe each independently selected from hydrogen, a methyl group, an ethylgroup, an n-propyl group, an n-butyl group, a phenyl group, a naphthylgroup, an anthryl group, a pyrenyl group, a phenanthrenyl group, afluorenyl group, a carbazolyl group, —N(Q₁)(Q₂), and —Si(Q₃)(Q₄)(Q₅);and

a phenyl group, a naphthyl group, an anthryl group, a pyrenyl group, aphenanthrenyl group, a fluorenyl group, and a carbazolyl group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a cyano group, a nitro group, a methyl group, a phenyl group, and anaphthyl group,

where Q₁ to Q₅ may be each independently selected from a C₁-C₆₀ alkylgroup, a C₆-C₆₀ aryl group, a monovalent non-aromatic condensedpolycyclic group, and a monovalent non-aromatic condensedheteropolycyclic group, but they are not limited thereto.

In some embodiments, R₁₃ to R₁₇ and R₂₃ to R₂₆ in Formulae 1 and 2-1 to2-5 may be each independently selected from hydrogen, a methyl group, aphenyl group, a naphthyl group, a carbazolyl group, —N(Q₁)(Q₂), and—Si(Q₃)(Q₄)(Q₅),

where Q₁ to Q₅ may be each independently selected from a methyl group,an ethyl group, a phenyl group, and a naphthyl group, but they are notlimited thereto.

In some embodiments, R₁₃ to R₁₇ and R₂₃ to R₂₆ in Formulae 1 and 2-1 to2-5 may be each independently hydrogen, but they are not limitedthereto.

b13 to b16 and b23 to b25 in Formulae 1 and 2-1 to 2-5 may be eachindependently selected from 1, 2, 3, and 4.

For example, R_(HT) in Formulae 1 and 2-1 to 2-5 may be selected from aphenyl group, a pentalenyl group, an indenyl group, a naphthyl group, anazulenyl group, a heptalenyl group, an indacenyl group, an acenaphthylgroup, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenylgroup, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenylgroup, an anthracenyl group, a fluoranthenyl group, a triphenylenylgroup, a pyrenyl group, a chrysenyl group, a naphthacenyl group, apicenyl group, a perylenyl group, a pentaphenyl group, a hexacenylgroup, a pentacenyl group, a rubicenyl group, a coronenyl group, anovalenyl group, a thiophenyl group, a furanyl group, a carbazolyl group,a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, adibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolylgroup, a thianthrenyl group, a phenoxathinyl group, and adibenzodioxinyl group;

a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group,an azulenyl group, a heptalenyl group, an indacenyl group, anacenaphthyl group, a fluorenyl group, a spiro-fluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, aphenanthrenyl group, an anthracenyl group, a fluoranthenyl group, atriphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenylgroup, a picenyl group, a perylenyl group, a pentaphenyl group, ahexacenyl group, a pentacenyl group, a rubicenyl group, a coronenylgroup, an ovalenyl group, a thiophenyl group, a furanyl group, acarbazolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a thianthrenyl group, a phenoxathinylgroup, and a dibenzodioxinyl group, each substituted with at least oneselected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid or a salt thereof, a sulfonic acid or a saltthereof, a phosphoric acid or a salt thereof, a C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a phenyl group, a naphthyl group, a fluorenylgroup, a carbazolyl group, —N(Q₄₁)(Q₄₂), —Si(Q₄₃)(Q₄₄)(Q₄₅), and—B(Q₄₆)(Q₄₇); and

a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group,an azulenyl group, a heptalenyl group, an indacenyl group, anacenaphthyl group, a fluorenyl group, a spiro-fluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, aphenanthrenyl group, an anthracenyl group, a fluoranthenyl group, atriphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenylgroup, a picenyl group, a perylenyl group, a pentaphenyl group, ahexacenyl group, a pentacenyl group, a rubicenyl group, a coronenylgroup, an ovalenyl group, a thiophenyl group, a furanyl group, acarbazolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a thianthrenyl group, a phenoxathinylgroup, and a dibenzodioxinyl group, each substituted with at least oneselected from a phenyl group, a naphthyl group, a fluorenyl group, and acarbazolyl group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a nitro group, an aminogroup, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, aphosphoric acid or a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxygroup, a phenyl group, a naphthyl group, a fluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a carbazolyl group,—N(Q₅₁)(Q₅₂), —Si(Q₅₃)(Q₅₄)(Q₅₅), and —B(Q₅₆)(Q₅₇);

where Q₄₁ to Q₄₇ and Q₅₁ to Q₅₇ may be each independently selected froma C₁-C₆₀ alkyl group, a C₆-C₆₀ aryl group, a monovalent non-aromaticcondensed polycyclic group, and a monovalent non-aromatic condensedheteropolycyclic group, but embodiments of the present invention are notlimited thereto.

In some embodiments, R_(HT) in Formulae 1 and 2-1 to 2-5 may be selectedfrom a phenyl group, a naphthyl group, a fluorenyl group, aphenanthrenyl group, an anthracenyl group, a triphenylenyl group, acarbazolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a thianthrenyl group, aphenoxathinyl group and a dibenzodioxinyl group;

a phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenylgroup, an anthracenyl group, a triphenylenyl group, a carbazolyl group,a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, adibenzothiophenyl group, a thianthrenyl group, a phenoxathinyl group,and a dibenzodioxinyl group, each substituted with at least one selectedfrom deuterium, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenylgroup, a naphthyl group, a fluorenyl group, a carbazolyl group,—N(Q₄₁)(Q₄₂), and —Si(Q₄₃)(Q₄₄)(Q₄₅); and

a phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenylgroup, an anthracenyl group, a triphenylenyl group, a carbazolyl group,a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, adibenzothiophenyl group, a thianthrenyl group, a phenoxathinyl group,and a dibenzodioxinyl group, each substituted with at least one selectedfrom a phenyl group, a naphthyl group, a fluorenyl group and acarbazolyl group, each substituted with at least one selected fromdeuterium, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group,a naphthyl group, —N(Q₅₁)(Q₅₂), and —Si(Q₅₃)(Q₅₄)(Q₅₅);

where Q₄₁ to Q₄₅ and Q₅₁ to Q₅₅ may be each independently selected froma methyl group, an ethyl group, an n-propyl group, an iso-propyl group,an n-butyl group, an iso-butyl group, a sec-butyl group, a tert-butylgroup, a phenyl group, a biphenyl group, a naphthyl group, and afluorenyl group, but embodiments of the present invention are notlimited thereto.

In some embodiments, R_(HT) in Formulae 1 and 2-1 to 2-5 may be selectedfrom groups represented by Formulae 5-1 to 5-12, but embodiments are notlimited thereto:

In Formulae 5-1 to 5-12,

X₅₁ is selected from a single bond, N(R₅₄), C(R₅₄)(R₅₅), O, and S;

X₅₂ is selected from N(R₅₆), C(R₅₆)(R₅₇), O, and S;

R₅₁ to R₅₇ may be each independently selected from:

deuterium, a C₁-C₂₀ alkyl group, a phenyl group, a naphthyl group, afluorenyl group, a carbazolyl group, —N(Q₄₁)(Q₄₂), and—Si(Q₄₃)(Q₄₄)(Q₄₅); and

a phenyl group, a naphthyl group, a fluorenyl group, and a carbazolylgroup, each substituted with at least one selected from deuterium, aC₁-C₂₀ alkyl group, a phenyl group, a naphthyl group, —N(Q₅₁)(Q₅₂), and—Si(Q₅₃)(Q₅₄)(Q₅₅);

where Q₄₁ to Q₄₅ and Q₅₁ to Q₅₅ are each independently selected from amethyl group, an ethyl group, an n-propyl group, an iso-propyl group, ann-butyl group, an iso-butyl group, a sec-butyl group, a tert-butylgroup, a phenyl group, a biphenyl group, a naphthyl group, and afluorenyl group;

b51 may be selected from 1, 2, 3, 4, and 5;

b52 may be selected from 1, 2, 3, 4, 5, 6, and 7;

b53 may be selected from 1, 2, and 3;

b54 may be selected from 1, 2, 3, and 4;

b55 may be selected from 1, 2, 3, 4, 5, and 6; and

* indicates a binding site to a neighboring atom.

For example, R_(ET) in Formulae 1 and 2-1 to 2-5 may be selected from apyrrolyl group, an imidazolyl group, a pyrazolyl group, a thiazolylgroup, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, an isoindolyl group, an indolyl group, an indazolyl group, apurinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, abenzophenanthrolinyl group, a phenazinyl group, a benzimidazolyl group,a naphthoimidazolyl group, a benzothiazolyl group, an isobenzothiazolylgroup, a benzoxazolyl group, an isobenzoxazolyl group, a triazolylgroup, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, animidazopyridinyl group, an imidazopyrimidinyl group, animidazoquinolinyl group, an imidazoisoquinolinyl group, apyridobenzofuranyl group, a pyrimidobenzofuranyl group, apyridobenzothiophenyl group, and a pyrimidobenzothiophenyl group;

a pyrrolyl group, an imidazolyl group, a pyrazolyl group, a thiazolylgroup, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, an isoindolyl group, an indolyl group, an indazolyl group, apurinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, abenzophenanthrolinyl group, a phenazinyl group, a benzimidazolyl group,a naphthoimidazolyl group, a benzothiazolyl group, an isobenzothiazolylgroup, a benzoxazolyl group, an isobenzoxazolyl group, a triazolylgroup, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, animidazopyridinyl group, an imidazopyrimidinyl group, animidazoquinolinyl group, an imidazoisoquinolinyl group, apyridobenzofuranyl group, a pyrimidobenzofuranyl group, apyridobenzothiophenyl group, and a pyrimidobenzothiophenyl group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a naphthylgroup, a fluorenyl group, a carbazolyl group, a pyridinyl group, apyrimidinyl group, a triazinyl group, —N(Q₄₁)(Q₄₂), —Si(Q₄₃)(Q₄₄)(Q₄₅),and —B(Q₄₆)(Q₄₇); and

a pyrrolyl group, an imidazolyl group, a pyrazolyl group, a thiazolylgroup, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, an isoindolyl group, an indolyl group, an indazolyl group, apurinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, abenzophenanthrolinyl group, a phenazinyl group, a benzimidazolyl group,a naphthoimidazolyl group, a benzothiazolyl group, an isobenzothiazolylgroup, a benzoxazolyl group, an isobenzoxazolyl group, a triazolylgroup, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, animidazopyridinyl group, an imidazopyrimidinyl group, animidazoquinolinyl group, an imidazoisoquinolinyl group, apyridobenzofuranyl group, a pyrimidobenzofuranyl group, apyridobenzothiophenyl group, and a pyrimidobenzothiophenyl group, eachsubstituted with at least one selected from a phenyl group, a naphthylgroup, a fluorenyl group, a carbazolyl group, a pyridinyl group, apyrimidinyl group, and a triazinyl group, each substituted with at leastone selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid or a salt thereof, a sulfonic acid or a saltthereof, a phosphoric acid or a salt thereof, a C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a phenyl group, a naphthyl group, a fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a carbazolylgroup, a pyridinyl group, a pyrimidinyl group, a triazinyl group,—N(Q₅₁)(Q₅₂), —Si(Q₅₃)(Q₅₄)(Q₅₅), and —B(Q₅₆)(Q₅₇);

where Q₄₁ to Q₄₇ and Q₅₁ to Q₅₇ may be each independently selected froma C₁-C₆₀ alkyl group, a C₆-C₆₀ aryl group, a monovalent non-aromaticcondensed polycyclic group, and a monovalent non-aromatic condensedheteropolycyclic group, but embodiments of the present invention are notlimited thereto.

In some embodiments, R_(ET) in Formulae 1 and 2-1 to 2-5 may be selectedfrom a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, aquinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, anaphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, aphenanthridinyl group, a phenanthrolinyl group, a benzophenanthrolinylgroup, a benzimidazolyl group, a naphthoimidazolyl group, a triazinylgroup, an imidazopyridinyl group, an imidazopyrimidinyl group, animidazoquinolinyl group, and an imidazoisoquinolinyl group;

a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a quinolinylgroup, an isoquinolinyl group, a benzoquinolinyl group, a naphthyridinylgroup, a quinoxalinyl group, a quinazolinyl group, a phenanthridinylgroup, a phenanthrolinyl group, a benzophenanthrolinyl group, abenzimidazolyl group, a naphthoimidazolyl group, a triazinyl group, animidazopyridinyl group, an imidazopyrimidinyl group, animidazoquinolinyl group, and imidazoisoquinolinyl group, eachsubstituted with at least one selected from deuterium, a C₁-C₂₀ alkylgroup, a phenyl group, a naphthyl group, a fluorenyl group, a carbazolylgroup, a pyridinyl group, —N(Q₄₁)(Q₄₂), and —Si(Q₄₃)(Q₄₄)(Q₄₅); and

a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a quinolinylgroup, an isoquinolinyl group, a benzoquinolinyl group, a naphthyridinylgroup, a quinoxalinyl group, a quinazolinyl group, a phenanthridinylgroup, a phenanthrolinyl group, a benzophenanthrolinyl group, abenzimidazolyl group, a naphthoimidazolyl group, a triazinyl group, animidazopyridinyl group, an imidazopyrimidinyl group, animidazoquinolinyl group, and an imidazoisoquinolinyl group, eachsubstituted with at least one selected from a phenyl group, a naphthylgroup, a fluorenyl group, a carbazolyl group and a pyridinyl group, eachsubstituted with at least one selected from deuterium, a C₁-C₂₀ alkylgroup, a phenyl group, a naphthyl group, a pyridinyl group,—N(Q₅₁)(Q₅₂), and —Si(Q₅₃)(Q₅₄)(Q₅₅);

where Q₄₁ to Q₄₅ and Q₅₁ to Q₅₅ may be each independently selected froma methyl group, an ethyl group, an n-propyl group, an iso-propyl group,an n-butyl group, an iso-butyl group, a sec-butyl group, a tert-butylgroup, a phenyl group, a biphenyl group, a naphthyl group, and afluorenyl group, but embodiments of the present invention are notlimited thereto.

In some embodiments, R_(ET) in Formulae 1 and 2-1 to 2-5 may be selectedfrom groups represented by Formulae 6-1 to 6-63, but is not limitedthereto:

In Formulae 6-1 to 6-63,

R₆₁ to R₆₃ may be each independently selected from:

deuterium, a C₁-C₂₀ alkyl group, a phenyl group, a naphthyl group, afluorenyl group, a carbazolyl group, a pyridinyl group, —N(Q₄₁)(Q₄₂),and —Si(Q₄₃)(Q₄₄)(Q₄₅); and

a phenyl group, a naphthyl group, a fluorenyl group, a carbazolyl group,a pyridinyl group, each substituted with at least one selected fromdeuterium, a C₁-C₂₀ alkyl group, a phenyl group, a naphthyl group, apyridinyl group, —N(Q₅₁)(Q₅₂), and —Si(Q₅₃)(Q₅₄)(Q₅₅);

where Q₄₁ to Q₄₅ and Q₅₁ to Q₅₅ may be each independently selected froma methyl group, an ethyl group, an n-propyl group, an iso-propyl group,an n-butyl group, an iso-butyl group, a sec-butyl group, a tert-butylgroup, a phenyl group, a biphenyl group, a naphthyl group, and afluorenyl group;

b61 may be selected from 1, 2, 3, and 4; and

b62 may be selected from 1, 2, and 3;

b63 may be selected from 1, 2, 3, 4, 5, and 6;

b64 may be selected from 1, 2, 3, 4, and 5;

b65 may be selected from 1 and 2; and

* indicates a binding site to a neighboring atom.

For example, the first compound may be represented by Formula 1-1 below,but is not limited thereto:

In Formula 1-1,

descriptions of A₁₁, A₁₄, X₁₁, L₁₁, a11, R₁₁, R₁₃ to R₁₆, b11, and b13to b16 are the same as described above.

In some embodiments, the second compound may be represented by any oneof Formulae 2-11 to 2-15 below, but embodiments of the present inventionare not limited thereto:

In Formulae 2-11 to 2-15,

descriptions of A₂₁, A₂₂, L₂₁, a21, X₂₁, R₂₁, R₂₃, R₂₅, b21, b23, andb25 are the same as described above.

In some embodiments, the first compound may be selected from Compounds101A to 206A below, but is not limited thereto:

In some embodiments, the second compound may be selected from Compounds301A to 369A below, but is not limited thereto:

In some embodiments, neither the first compound nor the second compoundmay include a cyano group.

When the first compound and the second compound include a cyano group,due to very strong electron affinity of the cyano group, lowestunoccupied molecular orbital (LUMO) levels of the compounds may bedecreased to below 3.0 eV, which may not be appropriate for a LUMO levelof a phosphorescent dopant. Accordingly, an organic light-emittingdevice including a compound having a cyano group as a host may have arelatively low efficiency.

Also, when the first compound and the second compound include a cyanogroup, due to the very strong electron affinity of the cyano group, thepolarity of the compounds may be too high, and thus electric stabilitymay be decreased. Accordingly, an organic light-emitting deviceincluding a compound having a cyano group as a host may have a decreasedlifespan.

On the other hand, when neither the first compound nor the secondcompound includes a cyano group, their LUMO levels may be in a range ofabout 2.6 eV to about 3.0 eV, which may be appropriate for a LUMO levelfor a phosphorescent dopant.

When neither the first compound nor the second compound includes a cyanogroup, their electric stability may be increased.

Accordingly, since neither the first compound nor the second compoundincludes a cyano group, an organic light-emitting device including thefirst compound and the second compound may have high efficiency and alonger lifespan.

In some embodiments, the host may include a first compound representedby Formula 1 and a second compound represented by any one of Formulae2-1 to 2-5;

A₁₁, A₁₂, A₁₃, A₁₄, A₂₁, and A₂₂ in Formulae 1, and 2-1 to 2-5 may beeach independently selected from a benzene, a naphthalene, a pyridine, apyrimidine, a quinoline, an isoquinoline, a 2,6-naphthyridine, a1,8-naphthyridine, a 1,5-naphthyridine, a 1,6-naphthyridine, a1,7-naphthyridine, a 2,7-naphthyridine, a quinoxaline, a phthalazine, aquinazoline, and a cinnoline.

For example, A₁₁, A₁₂, A₁₃, A₁₄, A₂₁, and A₂₂ in Formulae 1, and 2-1 to2-5 may be each independently selected from a benzene, a naphthalene, apyridine, a pyrimidine, a quinoline, an isoquinoline, a2,6-naphthyridine, a 1,8-naphthyridine, a 1,5-naphthyridine, a1,6-naphthyridine, a 1,7-naphthyridine, a 2,7-naphthyridine, aquinoxaline, and a quinazoline.

In some embodiments, in Formula 1, A₁₁ and A₁₄ may be each independentlyselected from a benzene, a naphthalene, a pyridine, a pyrimidine, aquinoline, an isoquinoline, a 2,6-naphthyridine, a 1,8-naphthyridine, a1,5-naphthyridine, a 1,6-naphthyridine, a 1,7-naphthyridine, a2,7-naphthyridine, a quinoxaline, and a quinazoline, and A₁₂ and A₁₃ maybe each independently a benzene, but they are not limited thereto.

In some embodiments, in Formula 1, A₁₁ and A₁₄ may be each independentlyselected from a benzene and a naphthalene, and A₁₂ and A₁₃ may be eachindependently a benzene, but they are not limited thereto.

In some embodiments, A₁₁ to A₁₄ in Formula 1 may be each independently abenzene, but they are not limited thereto.

In some embodiments, A₂₁ and A₂₂ in Formulae 2-1 to 2-5 may be eachindependently a benzene, but they are not limited thereto.

X₁₁ in Formula 1 may be selected from O, S, N[(L₁₂)_(a12)-(R₁₂)_(b12)],C[(L₁₂)_(a12)-(R₁₂)_(b12)][R₁₇], Si[(L₁₂)_(a12)-(R₁₂)_(b12)][R₁₇],P[(L₁₂)_(a12)-(R₁₂)_(b12)], B[(L₁₂)_(a12)-(R₁₂)_(b12)], andP(═O)[(L₁₂)_(a12)-(R₁₂)_(b12)].

For example, X₁₁ in Formula 1 may be selected from O, S,N[(L₁₂)_(a12)-(R₁₂)_(b12)], C[(L₁₂)_(a12)-(R₁₂)_(b12)][R₁₇],Si[(L₁₂)_(a2)-(R₁₂)_(b2)][R₁₇], P[(L₁₂)_(a12)-(R₁₂)_(b12)],B[(L₁₂)_(a12)-(R₁₂)_(b12)], and P(═O)[(L₁₂)_(a12)-(R₁₂)_(b12)]; and R₁₂and R₁₇ may be optionally connected to each other to form a saturated orunsaturated ring, but they are not limited thereto.

In some embodiments, X₁₁ in Formula 1 may be selected from O, S,N[(L₁₂)_(a12)-(R₁₂)_(b12)], and C[(L₁₂)_(a12)-(R₁₂)_(b12)][R₁₇], but isnot limited thereto.

X₂₁ in Formulae 2-1 to 2-5 may be selected from O, S,N[(L₂₂)_(a22)-(R₂₂)_(b22)], C[(L₂₂)_(a22)-(R₂₂)_(b22)][R₂₆],Si[(L₂₂)_(a22)-(R₂₂)_(b22)][R₂₆], P[(L₂₂)_(a22)-(R₂₂)_(b22)],B[(L₂₂)_(a22)-(R₂₂)_(b22)], and P(═O)[(L₂₂)_(a22)-(R₂₂)_(b22)].

For example, X₂₁ in Formulae 2-1 to 2-5 may be selected from O, S,N[(L₂₂)_(a22)-(R₂₂)_(b22)] and C[(L₂₂)_(a22)-(R₂₂)_(b22)][R₂₆], but isnot limited thereto.

L₁₁ to L₁₃, L₂₁, and L₂₂ in Formulae 1 and 2-1 to 2-5 may be eachindependently selected from a substituted or unsubstituted C₃-C₁₀cycloalkylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group; and

at least one substituent of the substituted C₃-C₁₀ cycloalkylene group,the substituted C₁-C₁₀ heterocycloalkylene group, the substituted C₃-C₁₀cycloalkenylene group, the substituted C₁-C₁₀ heterocycloalkenylenegroup, the substituted C₆-C₆₀ arylene group, the substituted C₁-C₆₀heteroarylene group, the substituted divalent non-aromatic condensedpolycyclic group, and the substituted divalent non-aromatic condensedheteropolycyclic group may be selected from:

deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid group or a salt thereof, a sulfonic acid groupor a salt thereof, a phosphoric acid group or a salt thereof, a C₁-C₆₀alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and aC₁-C₆₀ alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid ora salt thereof, a phosphoric acid or a salt thereof, a C₃-C₁₀ cycloalkylgroup, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, aC₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxygroup, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₁₁)(Q₁₂), —Si(Q₁₃)(Q₁₄)(Q₁₅), and—B(Q₁₆)(Q₁₇);

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, aC₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group,a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₂₁)(Q₂₂), —Si(Q₂₃)(Q₂₄)(Q₂₅), and—B(Q₂₆)(Q₂₇); and

—N(Q₃₁)(Q₃₂), —Si(Q₃₃)(Q₃₄)(Q₃₅), and —B(Q₃₆)(Q₃₇);

where Q₁₁ to Q₁₇, Q₂₁ to Q₂₇, and Q₃₁ to Q₃₇ may be each independentlyselected from hydrogen, a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkoxy group, aC₆-C₆₀ aryl group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromaticcondensed polycyclic group, and a monovalent non-aromatic condensedheteropolycyclic group.

For example, L₁₁ to L₁₃, L₂₁, and L₂₂ in Formulae 1 and 2-1 to 2-5 maybe each independently selected from a phenylene group, a naphthylenegroup, a fluorenylene group, a phenanthrenylene group, a anthracenylenegroup, a triphenylenylene group, a pyrenylene group, a chrysenylenegroup, a pyrrolylene group, a thiophenylene group, a furanylene group,an imidazolylene group, a pyridinylene group, a pyrazinylene group, apyrimidinylene group, a pyridazinylene group, an indolylene group, aquinolinylene group, an isoquinolinylene group, a benzoquinolinylenegroup, a phenanthridinylene group, an acridinylene group, aphenanthrolinylene group, a benzofuranylene group, a benzothiophenylenegroup, a triazolylene group, a tetrazolylene group, a triazinylenegroup, a dibenzofuranylene group, and a dibenzothiophenylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, aphenanthrenylene group, an anthracenylene group, a triphenylenylenegroup, a pyrenylene group, a chrysenylene group, a pyrrolylene group, athiophenylene group, a furanylene group, an imidazolylene group, apyridinylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, an indolylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phenanthridinylenegroup, an acridinylene group, a phenanthrolinylene group, abenzofuranylene group, a benzothiophenylene group, a triazolylene group,a tetrazolylene group, a triazinylene group, a dibenzofuranylene group,and a dibenzothiophenylene group, each substituted with at least oneselected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid or a salt thereof, asulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, aC₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a naphthylgroup, a fluorenyl group, a spiro-fluorenyl group, a phenalenyl group, aphenanthrenyl group, an anthracenyl group, a fluoranthenyl group, atriphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenylgroup, a pentaphenyl group, a hexacenyl group, a pentacenyl group, apyrrolyl group, a thiophenyl group, a furanyl group, an imidazolylgroup, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, anoxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinylgroup, a pyrimidinyl group, a pyridazinyl group, an indolyl group, anindazolyl group, a quinolinyl group, an isoquinolinyl group, acarbazolyl group, a benzoquinolinyl group, a phthalazinyl group, anaphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a benzimidazolyl group, a benzofuranyl group, abenzothiophenyl group, a benzoxazolyl group, a triazolyl group, atetrazolyl group, an oxadiazolyl group, a triazinyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl groupand a dibenzocarbazolyl group, but they are not limited thereto.

In some embodiments, L₁₁ to L₁₃, L₂₁, and L₂₂ in Formulae 1 and 2-1 to2-5 may be each independently selected from a phenylene group, anaphthylene group, a fluorenylene group, a dibenzofuranylene group, anda dibenzothiophenylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, adibenzofuranylene group, and a dibenzothiophenylene group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a cyano group, a nitro group, a C₁-C₂₀ alkyl group, a phenyl group, anda naphthyl group, but they are not limited thereto.

In some embodiments, L₁₁ to L₁₃, L₂₁, and L₂₂ in Formulae 1 and 2-1 to2-5 may be each independently selected from groups represented byFormulae 3-1 to 3-19, but they are not limited thereto:

In Formulae 3-1 to 3-19,

X₃₁ may be selected from O, S, and C(R₃₃)(R₃₄);

R₃₁ to R₃₄ may be each independently selected from hydrogen, deuterium,—F, —Cl, —Br, —I, a cyano group, a nitro group, a methyl group, an ethylgroup, an n-propyl group, an iso-propyl group, an n-butyl group,iso-butyl group, a sec-butyl group, a tert-butyl group, a phenyl group,and a naphthyl group;

b31 may be selected from 1, 2, 3, and 4;

b32 may be selected from 1, 2, 3, 4, 5, and 6;

b33 may be selected from 1, 2, and 3; and

* and *′ each indicate a binding site to a neighboring atom.

In some embodiments, L₁₁ to L₁₃, L₂₁, and L₂₂ in Formulae 1 and 2-1 to2-5 may be each independently selected from groups represented byFormulae 4-1 to 4-13, but they are not limited thereto:

In Formulae 4-1 to 4-13,

* and *′ each indicate a binding site to a neighboring atom.

a11 in Formula 1 indicates the number of L₁₁, and a11 may be selectedfrom 0, 1, 2, 3, 4, and 5. When a11 is 0, -(L₁₁)_(a11)- indicates asingle bond. When a11 is 2 or more, a plurality of L₁₁ may be identicalto or different from each other. For example, a11 in Formula 1 may beselected from 0 and 1, but is not limited thereto.

a12 in Formula 1 indicates the number of L₁₂, and a12 may be selectedfrom 0, 1, 2, 3, 4, and 5. When a12 is 0, -(L₁₂)_(a12)- is a singlebond. When a12 is 2 or more, a plurality of L₁₂ may be identical to ordifferent from each other. For example, a12 in Formula 1 may be selectedfrom 0 and 1, but is not limited thereto.

a13 in Formula 1 indicates the number of L₁₃, and a13 may be selectedfrom 0, 1, 2, 3, 4, and 5. When a13 is 0, -(L₁₃)_(a13)- indicates asingle bond. When a13 is 2 or more, a plurality of L₁₃ may be identicalto or different from each other. For example, a13 in Formula 1 may beselected from 0 and 1, but is not limited thereto. In some embodiments,a13 in Formula 1 may be 0, but is not limited thereto.

a21 in Formulae 2-1 to 2-5 indicates the number of L₂₁, and a21 may beselected from 0, 1, 2, 3, 4, and 5. When a21 is 0, -(L₂₁)_(a21)-indicates a single bond. When a21 is 2 or more, a plurality of L₂₁ maybe identical to or different from each other. For example, a21 inFormula 1 may be selected from 0 and 1, but is not limited thereto.

a22 in Formulae 2-1 to 2-5 indicates the number of L₂₂, and a22 may beselected from 0, 1, 2, 3, 4, and 5. When a22 is 0, -(L₂₂)_(a22)- is asingle bond. When a22 is 2 or more, a plurality of L₂₂ may be identicalto or different from each other. For example, a22 in Formula 1 may beselected from 0 and 1, but is not limited thereto.

In Formulae 1 and 2-1 to 2-5, R₁₁ and R₁₂ may be each independentlyR_(HT); R₂₁ and R₂₂ may be each independently selected from R_(HT) andR_(ET), provided that at least one selected from R₂₁ and R₂₂ is R_(ET);where R_(HT) is a hole transport group; and R_(ET) is an electrontransport group.

b11 in Formula 1 indicates the number of R₁₁, and b11 may be selectedfrom 1, 2, 3, and 4. When b11 is 2 or more, a plurality of R₁₁ may beidentical to or different from each other.

b12 in Formula 1 indicates the number of R₁₂, and b12 may be selectedfrom 0, 1, 2, 3, and 4. When b12 is 2 or more, a plurality of R₁₂ may beidentical to or different from each other.

b21 in Formulae 2-1 to 2-5 indicates the number of R₂₁, and may beselected from 1, 2, 3, and 4. When b21 is 2 or more, a plurality of R₂₁may be identical to or different from each other.

b22 in Formulae 2-1 to 2-5 indicates the number of R₂₂, and may beselected from 1, 2, 3, and 4. When b22 is 2 or more, a plurality of R₂₂may be identical to or different from each other.

R₁₃ to R₁₇ and R₂₃ to R₂₆ in Formulae 1 and 2-1 to 2-5 may be eachindependently selected from hydrogen, deuterium, —F, —Cl, —Br, —I, ahydroxyl group, a cyano group, a nitro group, an amino group, an amidinogroup, a hydrazine group, a hydrazone group, a carboxylic acid or a saltthereof, a sulfonic acid or a salt thereof, a phosphoric acid or a saltthereof, a substituted or unsubstituted C₁-C₆₀ alkyl group, asubstituted or unsubstituted C₂-C₆₀ alkenyl group, a substituted orunsubstituted C₂-C₆₀ alkynyl group, a substituted or unsubstitutedC₁-C₆₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀ cycloalkylgroup, a substituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted monovalent non-aromatic condensed polycyclic group, asubstituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group, —N(Q₁)(Q₂), —Si(Q₃)(Q₄)(Q₅), and —B(Q₆)(Q₇);

at least one substituent of the substituted C₁-C₆₀ alkyl group, thesubstituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀ alkynyl group,the substituted C₁-C₆₀ alkoxy group, the substituted C₃-C₁₀ cycloalkylgroup, the substituted C₁-C₁₀ heterocycloalkyl group, the substitutedC₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀ heterocycloalkenylgroup, the substituted C₆-C₆₀ aryl group, the substituted C₆-C₆₀ aryloxygroup, the substituted C₆-C₆₀ arylthio group, the substituted C₁-C₆₀heteroaryl group, the substituted a monovalent non-aromatic condensedpolycyclic group, and the substituted monovalent non-aromatic condensedheteropolycyclic group may be selected from:

deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid group or a salt thereof, a sulfonic acid groupor a salt thereof, a phosphoric acid group or a salt thereof, a C₁-C₆₀alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and aC₁-C₆₀ alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid ora salt thereof, a phosphoric acid or a salt thereof, a C₃-C₁₀ cycloalkylgroup, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, aC₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxygroup, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₁₁)(Q₁₂), —Si(Q₁₃)(Q₁₄)(Q₁₅), and—B(Q₁₆)(Q₁₇);

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, aC₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group,a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₂₁)(Q₂₂), —Si(Q₂₃)(Q₂₄)(Q₂₅), and—B(Q₂₆)(Q₂₇); and

—N(Q₃₁)(Q₃₂), —Si(Q₃₃)(Q₃₄)(Q₃₅), and —B(Q₃₆)(Q₃₇);

where Q₁ to Q₇, Q₁₁ to Q₁₇, Q₂₁ to Q₂₇ and Q₃₁ to Q₃₇ may be eachindependently selected from hydrogen, a C₁-C₆₀ alkyl group, a C₁-C₆₀alkoxy group, a C₆-C₆₀ aryl group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, and a monovalentnon-aromatic condensed heteropolycyclic group.

For example, R₁₃ to R₁₇ and R₂₃ to R₂₆ in Formulae 1 and 2-1 to 2-5 maybe each independently selected from hydrogen, a methyl group, an ethylgroup, an n-propyl group, an n-butyl group, a phenyl group, a naphthylgroup, an anthryl group, a pyrenyl group, a phenanthrenyl group, afluorenyl group, a carbazolyl group, —N(Q₁)(Q₂), and —Si(Q₃)(Q₄)(Q₅);and

a phenyl group, a naphthyl group, an anthryl group, a pyrenyl group, aphenanthrenyl group, a fluorenyl group, and a carbazolyl group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a cyano group, a nitro group, a methyl group, a phenyl group, and anaphthyl group,

where Q₁ to Q₅ may be each independently selected from a C₁-C₆₀ alkylgroup, a C₆-C₆₀ aryl group, a monovalent non-aromatic condensedpolycyclic group, and a monovalent non-aromatic condensedheteropolycyclic group, but they are not limited thereto.

In some embodiments, R₁₃ to R₁₇ and R₂₃ to R₂₆ in Formulae 1 and 2-1 to2-5 may be each independently selected from hydrogen, a methyl group, aphenyl group, a naphthyl group, a carbazolyl group, —N(Q₁)(Q₂), and—Si(Q₃)(Q₄)(Q₅),

where Q₁ to Q₅ may be each independently selected from a methyl group,an ethyl group, a phenyl group, and a naphthyl group, but they are notlimited thereto.

In some embodiments, R₁₃ to R₁₇ and R₂₃ to R₂₆ in Formulae 1 and 2-1 to2-5 may be each independently hydrogen, but they are not limitedthereto.

b13 to b16 and b23 to b25 in Formulae 1 and 2-1 to 2-5 may be eachindependently selected from 1, 2, 3, and 4.

For example, R_(HT) in Formulae 1 and 2-1 to 2-5 may be selected from aphenyl group, a pentalenyl group, an indenyl group, a naphthyl group, anazulenyl group, a heptalenyl group, an indacenyl group, an acenaphthylgroup, a fluorenyl group, a spiro-fluorenyl group, a benzofluorenylgroup, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenylgroup, an anthracenyl group, a fluoranthenyl group, a triphenylenylgroup, a pyrenyl group, a chrysenyl group, a naphthacenyl group, apicenyl group, a perylenyl group, a pentaphenyl group, a hexacenylgroup, a pentacenyl group, a rubicenyl group, a coronenyl group, anovalenyl group, a thiophenyl group, a furanyl group, a carbazolyl group,a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, adibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolylgroup, a thianthrenyl group, a phenoxathinyl group, and adibenzodioxinyl group;

a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group,an azulenyl group, a heptalenyl group, an indacenyl group, anacenaphthyl group, a fluorenyl group, a spiro-fluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, aphenanthrenyl group, an anthracenyl group, a fluoranthenyl group, atriphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenylgroup, a picenyl group, a perylenyl group, a pentaphenyl group, ahexacenyl group, a pentacenyl group, a rubicenyl group, a coronenylgroup, an ovalenyl group, a thiophenyl group, a furanyl group, acarbazolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a thianthrenyl group, a phenoxathinylgroup, and a dibenzodioxinyl group, each substituted with at least oneselected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid or a salt thereof, a sulfonic acid or a saltthereof, a phosphoric acid or a salt thereof, a C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a phenyl group, a naphthyl group, a fluorenylgroup, a carbazolyl group, —N(Q₄₁)(Q₄₂), —Si(Q₄₃)(Q₄₄)(Q₄₅), and—B(Q₄₆)(Q₄₇); and

a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group,an azulenyl group, a heptalenyl group, an indacenyl group, anacenaphthyl group, a fluorenyl group, a spiro-fluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, aphenanthrenyl group, an anthracenyl group, a fluoranthenyl group, atriphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenylgroup, a picenyl group, a perylenyl group, a pentaphenyl group, ahexacenyl group, a pentacenyl group, a rubicenyl group, a coronenylgroup, an ovalenyl group, a thiophenyl group, a furanyl group, acarbazolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a thianthrenyl group, a phenoxathinylgroup, and a dibenzodioxinyl group, each substituted with at least oneselected from a phenyl group, a naphthyl group, a fluorenyl group, and acarbazolyl group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a nitro group, an aminogroup, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, aphosphoric acid or a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxygroup, a phenyl group, a naphthyl group, a fluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a carbazolyl group,—N(Q₅₁)(Q₅₂), —Si(Q₅₃)(Q₅₄)(Q₅₅), and —B(Q₅₆)(Q₅₇);

where Q₄₁ to Q₄₇ and Q₅₁ to Q₅₇ may be each independently selected froma C₁-C₆₀ alkyl group, a C₆-C₆₀ aryl group, a monovalent non-aromaticcondensed polycyclic group, and a monovalent non-aromatic condensedheteropolycyclic group, but embodiments of the present invention are notlimited thereto.

In some embodiments, R_(HT) in Formulae 1 and 2-1 to 2-5 may be eachindependently selected from a phenyl group, a naphthyl group, afluorenyl group, a phenanthrenyl group, an anthracenyl group, atriphenylenyl group, a carbazolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a thianthrenyl group, a phenoxathinyl group and a dibenzodioxinylgroup;

a phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenylgroup, an anthracenyl group, a triphenylenyl group, a carbazolyl group,a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, adibenzothiophenyl group, a thianthrenyl group, a phenoxathinyl group,and a dibenzodioxinyl group, each substituted with at least one selectedfrom deuterium, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenylgroup, a naphthyl group, a fluorenyl group, a carbazolyl group,—N(Q₄₁)(Q₄₂), and —Si(Q₄₃)(Q₄₄)(Q₄₅); and

a phenyl group, a naphthyl group, a fluorenyl group, a phenanthrenylgroup, an anthracenyl group, a triphenylenyl group, a carbazolyl group,a benzofuranyl group, a benzothiophenyl group, a dibenzofuranyl group, adibenzothiophenyl group, a thianthrenyl group, a phenoxathinyl group,and a dibenzodioxinyl group, each substituted with at least one selectedfrom a phenyl group, a naphthyl group, a fluorenyl group and acarbazolyl group, each substituted with at least one selected fromdeuterium, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group,a naphthyl group, —N(Q₅₁)(Q₅₂), and —Si(Q₅₃)(Q₅₄)(Q₅₅);

where Q₄₁ to Q₄₅ and Q₅₁ to Q₅₅ may be each independently selected froma methyl group, an ethyl group, an n-propyl group, an iso-propyl group,an n-butyl group, an iso-butyl group, a sec-butyl group, a tert-butylgroup, a phenyl group, a biphenyl group, a naphthyl group, and afluorenyl group, but embodiments of the present invention are notlimited thereto.

In some embodiments, R_(HT) in Formulae 1 and 2-1 to 2-5 may be selectedfrom groups represented by Formulae 5-1 to 5-12, but embodiments of thepresent invention are not limited thereto:

In Formulae 5-1 to 5-12,

X₅₁ is selected from a single bond, N(R₅₄), C(R₅₄)(R₅₅), O, and S;

X₅₂ is selected from N(R₅₆), C(R₅₆)(R₅₇), O, and S;

R₅₁ to R₅₇ may be each independently selected from:

deuterium, a C₁-C₂₀ alkyl group, a phenyl group, a naphthyl group, afluorenyl group, a carbazolyl group, —N(Q₄₁)(Q₄₂), and—Si(Q₄₃)(Q₄₄)(Q₄₅); and

a phenyl group, a naphthyl group, a fluorenyl group, and a carbazolylgroup, each substituted with at least one selected from deuterium, aC₁-C₂₀ alkyl group, a phenyl group, a naphthyl group, —N(Q₅₁)(Q₅₂), and—Si(Q₅₃)(Q₅₄)(Q₅₅);

where Q₄₁ to Q₄₅ and Q₅₁ to Q₅₅ are each independently selected from amethyl group, an ethyl group, an n-propyl group, an iso-propyl group, ann-butyl group, an iso-butyl group, a sec-butyl group, a tert-butylgroup, a phenyl group, a biphenyl group, a naphthyl group, and afluorenyl group;

b51 may be selected from 1, 2, 3, 4, and 5;

b52 may be selected from 1, 2, 3, 4, 5, 6, and 7;

b53 may be selected from 1, 2, and 3;

b54 may be selected from 1, 2, 3, and 4;

b55 may be selected from 1, 2, 3, 4, 5, and 6; and

* indicates a binding site to a neighboring atom.

For example, R_(ET) in Formulae 1 and 2-1 to 2-5 may be selected from apyrrolyl group, an imidazolyl group, a pyrazolyl group, a thiazolylgroup, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, an isoindolyl group, an indolyl group, an indazolyl group, apurinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, abenzophenanthrolinyl group, a phenazinyl group, a benzimidazolyl group,a naphthoimidazolyl group, a benzothiazolyl group, an isobenzothiazolylgroup, a benzoxazolyl group, an isobenzoxazolyl group, a triazolylgroup, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, animidazopyridinyl group, an imidazopyrimidinyl group, animidazoquinolinyl group, an imidazoisoquinolinyl group, apyridobenzofuranyl group, a pyrimidobenzofuranyl group, apyridobenzothiophenyl group, and a pyrimidobenzothiophenyl group;

a pyrrolyl group, an imidazolyl group, a pyrazolyl group, a thiazolylgroup, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, an isoindolyl group, an indolyl group, an indazolyl group, apurinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, abenzophenanthrolinyl group, a phenazinyl group, a benzimidazolyl group,a naphthoimidazolyl group, a benzothiazolyl group, an isobenzothiazolylgroup, a benzoxazolyl group, an isobenzoxazolyl group, a triazolylgroup, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, animidazopyridinyl group, an imidazopyrimidinyl group, animidazoquinolinyl group, an imidazoisoquinolinyl group, apyridobenzofuranyl group, a pyrimidobenzofuranyl group, apyridobenzothiophenyl group, and a pyrimidobenzothiophenyl group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a naphthylgroup, a fluorenyl group, a carbazolyl group, a pyridinyl group, apyrimidinyl group, a triazinyl group, —N(Q₄₁)(Q₄₂), —Si(Q₄₃)(Q₄₄)(Q₄₅),and —B(Q₄₆)(Q₄₇); and

a pyrrolyl group, an imidazolyl group, a pyrazolyl group, a thiazolylgroup, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, an isoindolyl group, an indolyl group, an indazolyl group, apurinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, abenzophenanthrolinyl group, a phenazinyl group, a benzimidazolyl group,a naphthoimidazolyl group, a benzothiazolyl group, an isobenzothiazolylgroup, a benzoxazolyl group, an isobenzoxazolyl group, a triazolylgroup, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, animidazopyridinyl group, an imidazopyrimidinyl group, animidazoquinolinyl group, an imidazoisoquinolinyl group, apyridobenzofuranyl group, a pyrimidobenzofuranyl group, apyridobenzothiophenyl group, and a pyrimidobenzothiophenyl group, eachsubstituted with at least one selected from a phenyl group, a naphthylgroup, a fluorenyl group, a carbazolyl group, a pyridinyl group, apyrimidinyl group, and a triazinyl group, each substituted with at leastone selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid or a salt thereof, a sulfonic acid or a saltthereof, a phosphoric acid or a salt thereof, a C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a phenyl group, a naphthyl group, a fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a carbazolylgroup, a pyridinyl group, a pyrimidinyl group, a triazinyl group,—N(Q₅₁)(Q₅₂), —Si(Q₅₃)(Q₅₄)(Q₅₅), and —B(Q₅₆)(Q₅₇);

where Q₄₁ to Q₄₇ and Q₅₁ to Q₅₇ may be each independently selected froma C₁-C₆₀ alkyl group, a C₆-C₆₀ aryl group, a monovalent non-aromaticcondensed polycyclic group, and a monovalent non-aromatic condensedheteropolycyclic group, but embodiments of the present invention are notlimited thereto.

In some embodiments, R_(ET) in Formulae 1 and 2-1 to 2-5 may be selectedfrom a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, aquinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, anaphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, aphenanthridinyl group, a phenanthrolinyl group, a benzophenanthrolinylgroup, a benzimidazolyl group, a naphthoimidazolyl group, a triazinylgroup, an imidazopyridinyl group, an imidazopyrimidinyl group, animidazoquinolinyl group, and an imidazoisoquinolinyl group;

a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a quinolinylgroup, an isoquinolinyl group, a benzoquinolinyl group, a naphthyridinylgroup, a quinoxalinyl group, a quinazolinyl group, a phenanthridinylgroup, a phenanthrolinyl group, a benzophenanthrolinyl group, abenzimidazolyl group, a naphthoimidazolyl group, a triazinyl group, animidazopyridinyl group, an imidazopyrimidinyl group, animidazoquinolinyl group, and imidazoisoquinolinyl group, eachsubstituted with at least one selected from deuterium, a C₁-C₂₀ alkylgroup, a phenyl group, a naphthyl group, a fluorenyl group, a carbazolylgroup, a pyridinyl group, —N(Q₄₁)(Q₄₂), and —Si(Q₄₃)(Q₄₄)(Q₄₅); and

a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a quinolinylgroup, an isoquinolinyl group, a benzoquinolinyl group, a naphthyridinylgroup, a quinoxalinyl group, a quinazolinyl group, a phenanthridinylgroup, a phenanthrolinyl group, a benzophenanthrolinyl group, abenzimidazolyl group, a naphthoimidazolyl group, a triazinyl group, animidazopyridinyl group, an imidazopyrimidinyl group, animidazoquinolinyl group, and an imidazoisoquinolinyl group, eachsubstituted with at least one selected from a phenyl group, a naphthylgroup, a fluorenyl group, a carbazolyl group and a pyridinyl group, eachsubstituted with at least one selected from deuterium, a C₁-C₂₀ alkylgroup, a phenyl group, a naphthyl group, a pyridinyl group,—N(Q₅₁)(Q₅₂), and —Si(Q₅₃)(Q₅₄)(Q₅₅);

where Q₄₁ to Q₄₅ and Q₅₁ to Q₅₅ may be each independently selected froma methyl group, an ethyl group, an n-propyl group, an iso-propyl group,an n-butyl group, an iso-butyl group, a sec-butyl group, a tert-butylgroup, a phenyl group, a biphenyl group, a naphthyl group, and afluorenyl group, but embodiments of the present invention are notlimited thereto.

In some embodiments, R_(ET) in Formulae 1 and 2-1 to 2-5 may be selectedfrom groups represented by Formulae 6-1 to 6-63, but is not limitedthereto:

In Formulae 6-1 to 6-63,

R₆₁ to R₆₃ may be each independently selected from:

deuterium, a C₁-C₂₀ alkyl group, a phenyl group, a naphthyl group, afluorenyl group, a carbazolyl group, a pyridinyl group, —N(Q₄₁)(Q₄₂),and —Si(Q₄₃)(Q₄₄)(Q₄₅); and

a phenyl group, a naphthyl group, a fluorenyl group, a carbazolyl group,a pyridinyl group, each substituted with at least one selected fromdeuterium, a C₁-C₂₀ alkyl group, a phenyl group, a naphthyl group, apyridinyl group, —N(Q₅₁)(Q₅₂), and —Si(Q₅₃)(Q₅₄)(Q₅₅);

where Q₄₁ to Q₄₅ and Q₅₁ to Q₅₅ may be each independently selected froma methyl group, an ethyl group, an n-propyl group, an iso-propyl group,an n-butyl group, an iso-butyl group, a sec-butyl group, a tert-butylgroup, a phenyl group, a biphenyl group, a naphthyl group, and afluorenyl group;

b61 may be selected from 1, 2, 3, and 4; and

b62 may be selected from 1, 2, and 3;

b63 may be selected from 1, 2, 3, 4, 5, and 6;

b64 may be selected from 1, 2, 3, 4, and 5;

b65 may be selected from 1 and 2; and

* indicates a binding site to a neighboring atom.

For example, the first compound may be represented by Formula 1-1 below,but is not limited thereto:

In Formula 1-1,

descriptions of A₁₁, A₁₄, X₁₁, L₁₁, a11, R₁₁, R₁₃ to R₁₆, b11, and b13to b16 are the same as described above.

In some embodiments, the second compound may be represented by any oneof Formulae 2-11 to 2-15 below, but embodiments of the present inventionare not limited thereto:

In Formulae 2-11 to 2-15,

descriptions of A₂₁, A₂₂, L₂₁, a21, X₂₁, R₂₁, R₂₃, R₂₅, b21, b23, andb25 are the same as described above.

In some embodiments, the first compound may be selected from Compounds101B to 230B below, but is not limited thereto:

In some embodiments, the second compound may be selected from Compounds301B to 434B below, but is not limited thereto:

For example, neither the first compound nor the second compound mayinclude a cyano group.

When the first compound and the second compound include a cyano group,due to very strong electron affinity of the cyano group, lowestunoccupied molecular orbital (LUMO) levels of the compounds may bedecreased to below 3.0 eV, which may not be appropriate for a LUMO levelof a phosphorescent dopant. Accordingly, an organic light-emittingdevice including a compound having a cyano group as a host may have lowefficiency.

Also, when the first compound and the second compound include a cyanogroup, due to the very strong electron affinity of the cyano group, thepolarity of the compounds may be too high, and thus electric stabilitymay be decreased. Accordingly, an organic light-emitting deviceincluding a compound having a cyano group as a host may have a decreasedlifespan.

On the other hand, when neither the first compound nor the secondcompound includes a cyano group, their LUMO levels may be in a range ofabout 2.6 eV to about 3.0 eV, which may be appropriate for a LUMO levelfor a phosphorescent dopant.

When neither the first compound nor the second compound includes a cyanogroup, their electric stability may be increased.

Accordingly, when neither the first compound nor the second compoundincludes a cyano group, an organic light-emitting device including thefirst compound and the second compound may have high efficiency and alonger lifespan.

In some embodiments, efficiency and lifespan of an organiclight-emitting device are affected by the following factors: i) whetherelectrons and holes are balanced in an emission layer; and ii) whetheran emission region is widely or substantially evenly distributed in theemission layer, and is not disproportionately distributed so as to bepositioned closer to a hole transport layer or to an electron transportlayer.

The above factors may not be satisfied when only one kind of material isincluded in the emission layer. However, according to embodiments of thepresent invention, these factors are satisfied by a) including at leasttwo different materials as a host in the emission layer, and b)differentiating characteristics of substituents of the at least twodifferent materials.

Accordingly, when an emission layer includes (a) a first compound and asecond compound, wherein (b) (i) the first compound includes an electrontransport group and the second compound includes a hole transport group,or (ii) the first compound includes hole transport group and the secondcompound includes an electron transport group, the efficiency andlifespan of an organic light-emitting device may be improved.

For example, the second compound having the hole transport group mayhave a relatively wide energy gap, and the first compound having theelectron transport group may have a relatively narrow energy gap. Inthis case, the second compound may effectively control electrontransport characteristics of the first compound and may prevent orsubstantially reduce the possibility of an emission region of anemission layer from being positioned close to the interface between anhole transport layer and the emission layer, thus leading to higherefficiency and improved lifespan characteristics of the resultingorganic light-emitting device.

In embodiments where the first compound includes a relatively strongelectron transport group (for example, a triazine group) and the secondcompound includes the hole transport group, improved efficiency andlifespan characteristics of the organic light-emitting device may beobtained, and when the second compound including the hole transportgroup is included in a relatively large amount, optimal efficiency andlifespan characteristics may be obtained.

In some embodiments, when the first compound includes a relatively weakelectron transport group (for example, a pyridine group or a pyrimidinegroup) and the second compound includes the hole transport group,improved efficiency and lifespan characteristics may be obtained, andwhen the second compound including the hole transport group is includedin a relatively small amount, optimal efficiency and lifespancharacteristics may be obtained.

Accordingly, a weight ratio of the first compound to the second compoundmay vary depending on electric characteristics of the first compound andthe second compound.

In some embodiments, a weight ratio of the first compound to the secondcompound may be in a range of 1:10 to 10:1. In some embodiments, aweight ratio of the first compound to the second compound may be in arange of 1:9 to 9:1. In some embodiments, a weight ratio of the firstcompound to the second compound may be in a range of 2:8 to 8:2, 3:7 to7:3, 4:6 to 6:4, or 5:5, but is not limited thereto.

The dopant may be a phosphorescent dopant.

The phosphorescent dopant may include an organometallic compoundincluding at least one selected from iridium (Ir), platinum (Pt), osmium(Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu),terbium (Tb), thulium (Tm), rhodium (Rh), and copper (Cu);

For example, the phosphorescent dopant may include an organometalliccomplex represented by Formula 401 below:

In Formula 401,

M may be selected from iridium (Ir), platinum (Pt), osmium (Os),titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu), terbium(Tb), and thulium (Tm);

X₄₀₁ to X₄₀₄ may be each independently a nitrogen atom or a carbon atom;

A₄₀₁ and A₄₀₂ rings may be each independently selected from asubstituted or unsubstituted benzene, a substituted or unsubstitutednaphthalene, a substituted or unsubstituted fluorene, a substituted orunsubstituted spiro-fluorene, a substituted or unsubstituted indene, asubstituted or unsubstituted pyrrole, a substituted or unsubstitutedthiophene, a substituted or unsubstituted furan, a substituted orunsubstituted imidazole, a substituted or unsubstituted pyrazole, asubstituted or unsubstituted thiazole, a substituted or unsubstitutedisothiazole, a substituted or unsubstituted oxazole, a substituted orunsubstituted isoxazole, a substituted or unsubstituted pyridine, asubstituted or unsubstituted pyrazine, a substituted or unsubstitutedpyrimidine, a substituted or unsubstituted pyridazine, a substituted orunsubstituted quinoline, a substituted or unsubstituted isoquinoline, asubstituted or unsubstituted benzoquinoline, a substituted orunsubstituted quinoxaline, a substituted or unsubstituted quinazoline, asubstituted or unsubstituted carbazole, a substituted or unsubstitutedbenzoimidazole, a substituted or unsubstituted benzofuran, a substitutedor unsubstituted benzothiophene, a substituted or unsubstitutedisobenzothiophene, a substituted or unsubstituted benzoxazole, asubstituted or unsubstituted isobenzoxazole, a substituted orunsubstituted triazole, a substituted or unsubstituted oxadiazole, asubstituted or unsubstituted triazine, a substituted or unsubstituteddibenzofuran, and a substituted or unsubstituted dibenzothiophene; and

at least one substituent of the substituted benzene, substitutednaphthalene, substituted fluorene, substituted spiro-fluorene,substituted indene, substituted pyrrole, substituted thiophene,substituted furan, substituted imidazole, substituted pyrazole,substituted thiazole, substituted isothiazole, substituted oxazole,substituted isoxazole, substituted pyridine, substituted pyrazine,substituted pyrimidine, substituted pyridazine, substituted quinoline,substituted isoquinoline, substituted benzoquinoline, substitutedquinoxaline, substituted quinazoline, substituted carbazole, substitutedbenzoimidazole, substituted benzofuran, substituted benzothiophene,substituted isobenzothiophene, substituted benzoxazole, substitutedisobenzoxazole, substituted triazole, substituted oxadiazole,substituted triazine, substituted dibenzofuran, and substituteddibenzothiophene may be selected from:

deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid group or a salt thereof, a sulfonic acid groupor a salt thereof, a phosphoric acid group or a salt thereof, a C₁-C₆₀alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and aC₁-C₆₀ alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid ora salt thereof, a phosphoric acid or a salt thereof, a C₃-C₁₀ cycloalkylgroup, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, aC₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxygroup, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₄₀₁)(Q₄₀₂), —Si(Q₄₀₃)(Q₄₀₄)(Q₄₀₅),and —B(Q₄₀₆)(Q₄₀₇);

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, aC₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group,a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₄₁₁1)(Q₄₁₂),—Si(Q₄₁₃)(Q₄₁₄)(Q₄₁₅), and —B(Q₄₁₆)(Q₄₁₇); and

—N(Q₄₂₁)(Q₄₂₂), —Si(Q₄₂₃)(Q₄₂₄)(Q₄₂₅), and —B(Q₄₂₆)(Q₄₂₇);

L₄₀₁ may be an organic ligand;

xc1 may be selected from 1, 2, and 3; and

xc2 may be selected from 0, 1, 2, and 3;

Q₄₀₁ to Q₄₀₇, Q₄₁₁ to Q₄₁₇, and Q₄₂₁ to Q₄₂₇ may be each independentlyselected from hydrogen, a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkoxy group, aC₆-C₆₀ aryl group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromaticcondensed polycyclic group, and a monovalent non-aromatic condensedheteropolycyclic group.

L₄₀₁ may be a monovalent, divalent, or trivalent organic ligand. Forexample, L₄₀₁ may be selected from a halogen ligand (for example, Cland/or F), a diketone ligand (for example, acetylacetonate,1,3-diphenyl-1,3-propanedionate, 2,2,6,6-tetramethyl-3,5-heptanedionate,and/or hexafluoroacetonate), a carboxylic acid ligand (for example,picolinate, dimethyl-3-pyrazolecarboxylate, and/or benzoate), a carbonmonooxide ligand, an isonitrile ligand, a cyano ligand, and aphosphorous ligand (for example, phosphine and/or phosphite), but is notlimited thereto.

When A₄₀₁ in Formula 401 has two or more substituents, the substituentsof A₄₀₁ may bind to each other to form a saturated or unsaturated ring.

When A₄₀₂ in Formula 401 has two or more substituents, the substituentsof A₄₀₂ may bind to each other to form a saturated or unsaturated ring.

When xc1 in Formula 401 is two or more, a plurality of ligands

may be identical to or different from each other. When xc1 in Formula401 is two or more, A₄₀₁ and/or A₄₀₂ of one ligand may be respectivelyconnected to A₄₀₁ and/or A₄₀₂ of other neighboring ligands, eitherdirectly (for example, via a single bond) or via a linker or linkinggroup (for example, a C₁-C₅ alkylene group, —N(R′)— (where R′ may be aC₁-C₁₀ alkyl group or a C₆-C₂₀ aryl group), and/or —C(═O)—)therebetween.

In some embodiments, M in Formula 401 may be selected from iridium (Ir),platinum (Pt), and osmium (Os), but is not limited thereto.

The phosphorescent dopant may include at least one of Compounds PD1 toPD82 below, but is not limited thereto:

An amount of the dopant in the emission layer may be, in general, in arange of about 0.01 to about 15 parts by weight based on 100 parts byweight of the host (calculated based on the sum of the first compoundand the second compound), but is not limited thereto.

A thickness of the emission layer may be in a range of about 100 Å toabout 1,000 Å, for example, about 200 Å to about 600 Å. When thethickness of the emission layer is within any of these ranges, excellentlight-emission characteristics may be obtained without a substantialincrease in driving voltage.

The electron transport region may include at least one selected from ahole blocking layer, an electron transport layer (ETL), and an electroninjection layer, but is not limited thereto.

For example, the electron transport region may have a structure ofelectron transport layer/electron injection layer or a structure of holeblocking layer/electron transport layer/electron injection layer, wherethe layers of each structure are sequentially stacked from the emissionlayer in the stated order, but is not limited thereto.

The electron transport region may include a hole blocking layer. Whenthe emission layer includes a phosphorescent dopant, the hole blockinglayer may be formed to prevent or substantially block the diffusion ofexcitons and/or holes into an electron transport layer.

When the electron transport region includes a hole blocking layer, thehole blocking layer may be formed on the emission layer by using one ormore suitable methods, such as vacuum deposition, spin coating casting,a Langmuir-Blodgett (LB) method, ink-jet printing, laser-printing,and/or laser-induced thermal imaging. When the hole blocking layer isformed by vacuum deposition and/or spin coating, deposition and coatingconditions for the hole blocking layer may be the same as (or similarto) the deposition and coating conditions for the hole injection layer.

The hole blocking layer may include, for example, at least one of BCPand Bphen, but is not limited thereto.

A thickness of the hole blocking layer may be in a range of about 20 Åto about 1,000 Å, for example, about 30 Å to about 300 Å. When thethickness of the hole blocking layer is within any of these ranges, thehole blocking layer may have excellent hole blocking characteristicswithout a substantial increase in driving voltage.

The electron transport region may include an electron transport layer.The electron transport layer may be formed on the emission layer or thehole blocking layer by using one or more suitable methods, such asvacuum deposition, spin coating casting, a LB method, ink-jet printing,laser-printing, and/or laser-induced thermal imaging. When the electrontransport layer is formed by vacuum deposition and/or spin coating,deposition and coating conditions for the electron transport layer maybe the same as (or similar to) the deposition and coating conditions forthe hole injection layer.

The electron transport layer may include a third compound represented byFormula 7 below:

L₇₁ in Formula 7 may be selected from a substituted or unsubstitutedC₃-C₁₀ cycloalkylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group;

at least one substituent of the substituted C₃-C₁₀ cycloalkylene group,the substituted C₁-C₁₀ heterocycloalkylene group, the substituted C₃-C₁₀cycloalkenylene group, the substituted C₁-C₁₀ heterocycloalkenylenegroup, the substituted C₆-C₆₀ arylene group, the substituted C₁-C₆₀heteroarylene group, the substituted divalent non-aromatic condensedpolycyclic group, and the substituted divalent non-aromatic condensedheteropolycyclic group may be selected from:

deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid group or a salt thereof, a sulfonic acid groupor a salt thereof, a phosphoric acid group or a salt thereof, a C₁-C₆₀alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and aC₁-C₆₀ alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid ora salt thereof, a phosphoric acid or a salt thereof, a C₃-C₁₀ cycloalkylgroup, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, aC₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxygroup, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₁₁)(Q₁₂), —Si(Q₁₃)(Q₁₄)(Q₁₅), and—B(Q₁₆)(Q₁₇);

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, aC₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group,a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₂₁)(Q₂₂), —Si(Q₂₃)(Q₂₄)(Q₂₅), and—B(Q₂₆)(Q₂₇); and

—N(Q₃₁)(Q₃₂), —Si(Q₃₃)(Q₃₄)(Q₃₅), and —B(Q₃₆)(Q₃₇);

where Q₁₁ to Q₁₇, Q₂₁ to Q₂₇, and Q₃₁ to Q₃₇ may be each independentlyselected from hydrogen, a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkoxy group, aC₆-C₆₀ aryl group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromaticcondensed polycyclic group, and a monovalent non-aromatic condensedheteropolycyclic group.

For example, L₇₁ in Formula 7 may be selected from a phenylene group, anaphthylene group, a fluorenylene group, a phenanthrenylene group, aanthracenylene group, a triphenylenylene group, a pyrenylene group, achrysenylene group, a pyrrolylene group, a thiophenylene group, afuranylene group, an imidazolylene group, a pyridinylene group, apyrazinylene group, a pyrimidinylene group, a pyridazinylene group, anindolylene group, a quinolinylene group, an isoquinolinylene group, abenzoquinolinylene group, a phenanthridinylene group, an acridinylenegroup, a phenanthrolinylene group, a benzofuranylene group, abenzothiophenylene group, a triazolylene group, a tetrazolylene group, atriazinylene group, a dibenzofuranylene group, and adibenzothiophenylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, aphenanthrenylene group, an anthracenylene group, a triphenylenylenegroup, a pyrenylene group, a chrysenylene group, a pyrrolylene group, athiophenylene group, a furanylene group, an imidazolylene group, apyridinylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, an indolylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phenanthridinylenegroup, an acridinylene group, a phenanthrolinylene group, abenzofuranylene group, a benzothiophenylene group, a triazolylene group,a tetrazolylene group, a triazinylene group, a dibenzofuranylene group,and a dibenzothiophenylene group, each substituted with at least oneselected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid or a salt thereof, asulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, aC₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a naphthylgroup, a fluorenyl group, a spiro-fluorenyl group, a phenalenyl group, aphenanthrenyl group, an anthracenyl group, a fluoranthenyl group, atriphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenylgroup, a pentaphenyl group, a hexacenyl group, a pentacenyl group, apyrrolyl group, a thiophenyl group, a furanyl group, an imidazolylgroup, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, anoxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinylgroup, a pyrimidinyl group, a pyridazinyl group, an indolyl group, anindazolyl group, a quinolinyl group, an isoquinolinyl group, acarbazolyl group, a benzoquinolinyl group, a phthalazinyl group, anaphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a benzimidazolyl group, a benzofuranyl group, abenzothiophenyl group, a benzoxazolyl group, a triazolyl group, atetrazolyl group, an oxadiazolyl group, a triazinyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolyl groupand a dibenzocarbazolyl group, but they are not limited thereto.

In some embodiments, L₇₁ in Formula 7 may be selected from a phenylenegroup, a naphthylene group, a fluorenylene group, a dibenzofuranylenegroup, and a dibenzothiophenylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, adibenzofuranylene group, and a dibenzothiophenylene group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a cyano group, a nitro group, a C₁-C₂₀ alkyl group, a phenyl group, anda naphthyl group, but they are not limited thereto.

According to some embodiments, L₇₁ in Formula 7 may be selected fromgroups represented by Formulae 3-1 to 3-19 below, but is not limitedthereto:

In Formulae 3-1 to 3-19,

X₃₁ may be selected from O, S, and C(R₃₃)(R₃₄);

R₃₁ to R₃₄ may be each independently selected from hydrogen, deuterium,—F, —Cl, —Br, —I, a cyano group, a nitro group, a methyl group, an ethylgroup, an n-propyl group, an iso-propyl group, an n-butyl group,iso-butyl group, a sec-butyl group, a tert-butyl group, a phenyl group,and a naphthyl group;

b31 may be selected from 1, 2, 3, and 4;

b32 may be selected from 1, 2, 3, 4, 5, and 6;

b33 may be selected from 1, 2, and 3; and

* and *′ each indicate a binding site to a neighboring atom.

According to some embodiments, L₇₁ in Formula 7 may be selected fromgroups represented by Formulae 4-1 to 4-13 below, but is not limitedthereto:

In Formulae 4-1 to 4-13,

* and *′ each indicate a binding site to a neighboring atom.

a71 in Formula 7 indicates the number of L₇₁, and a71 may be selectedfrom 0, 1, 2, 3, 4, and 5. When a71 is 0, (L₇₁)_(a71) indicates a singlebond. When a71 is 2 or more, a plurality of L₇₁ may be identical to ordifferent from each other. For example, a71 in Formula 7 may be selectedfrom 0, and 1, but is not limited thereto.

In Formula 7, R₇₁ may be R_(ET), where R_(ET) is an electron transportgroup.

For example, R_(ET) in Formula 7 may be selected from a pyrrolyl group,an imidazolyl group, a pyrazolyl group, a thiazolyl group, anisothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinylgroup, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, anisoindolyl group, an indolyl group, an indazolyl group, a purinyl group,a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, aphthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, aquinazolinyl group, a cinnolinyl group, a phenanthridinyl group, anacridinyl group, a phenanthrolinyl group, a benzophenanthrolinyl group,a phenazinyl group, a benzimidazolyl group, a naphthoimidazolyl group, abenzothiazolyl group, an isobenzothiazolyl group, a benzoxazolyl group,an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, anoxadiazolyl group, a triazinyl group, an imidazopyridinyl group, animidazopyrimidinyl group, an imidazoquinolinyl group, animidazoisoquinolinyl group, a pyridobenzofuranyl group, apyrimidobenzofuranyl group, a pyridobenzothiophenyl group, and apyrimidobenzothiophenyl group;

a pyrrolyl group, an imidazolyl group, a pyrazolyl group, a thiazolylgroup, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, an isoindolyl group, an indolyl group, an indazolyl group, apurinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, abenzophenanthrolinyl group, a phenazinyl group, a benzimidazolyl group,a naphthoimidazolyl group, a benzothiazolyl group, an isobenzothiazolylgroup, a benzoxazolyl group, an isobenzoxazolyl group, a triazolylgroup, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, animidazopyridinyl group, an imidazopyrimidinyl group, animidazoquinolinyl group, an imidazoisoquinolinyl group, apyridobenzofuranyl group, a pyrimidobenzofuranyl group, apyridobenzothiophenyl group, and a pyrimidobenzothiophenyl group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a naphthylgroup, a fluorenyl group, a carbazolyl group, a pyridinyl group, apyrimidinyl group, a triazinyl group, —N(Q₄₁)(Q₄₂), —Si(Q₄₃)(Q₄₄)(Q₄₅),and —B(Q₄₆)(Q₄₇); and

a pyrrolyl group, an imidazolyl group, a pyrazolyl group, a thiazolylgroup, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, an isoindolyl group, an indolyl group, an indazolyl group, apurinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, abenzophenanthrolinyl group, a phenazinyl group, a benzimidazolyl group,a naphthoimidazolyl group, a benzothiazolyl group, an isobenzothiazolylgroup, a benzoxazolyl group, an isobenzoxazolyl group, a triazolylgroup, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, animidazopyridinyl group, an imidazopyrimidinyl group, animidazoquinolinyl group, an imidazoisoquinolinyl group, apyridobenzofuranyl group, a pyrimidobenzofuranyl group, apyridobenzothiophenyl group, and a pyrimidobenzothiophenyl group, eachsubstituted with at least one selected from a phenyl group, a naphthylgroup, a fluorenyl group, a carbazolyl group, a pyridinyl group, apyrimidinyl group, and a triazinyl group, each substituted with at leastone selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid or a salt thereof, a sulfonic acid or a saltthereof, a phosphoric acid or a salt thereof, a C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a phenyl group, a naphthyl group, a fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a carbazolylgroup, a pyridinyl group, a pyrimidinyl group, a triazinyl group,—N(Q₅₁)(Q₅₂), —Si(Q₅₃)(Q₅₄)(Q₅₅), and —B(Q₅₆)(Q₅₇);

where Q₄₁ to Q₄₇ and Q₅₁ to Q₅₇ may be each independently selected froma C₁-C₆₀ alkyl group, a C₆-C₆₀ aryl group, a monovalent non-aromaticcondensed polycyclic group, and a monovalent non-aromatic condensedheteropolycyclic group, but embodiments of the present invention are notlimited thereto.

In some embodiments, R_(ET) in Formula 7 may be selected from apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a quinolinylgroup, an isoquinolinyl group, a benzoquinolinyl group, a naphthyridinylgroup, a quinoxalinyl group, a quinazolinyl group, a phenanthridinylgroup, a phenanthrolinyl group, a benzophenanthrolinyl group, abenzimidazolyl group, a naphthoimidazolyl group, a triazinyl group, animidazopyridinyl group, an imidazopyrimidinyl group, animidazoquinolinyl group, and an imidazoisoquinolinyl group;

a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a quinolinylgroup, an isoquinolinyl group, a benzoquinolinyl group, a naphthyridinylgroup, a quinoxalinyl group, a quinazolinyl group, a phenanthridinylgroup, a phenanthrolinyl group, a benzophenanthrolinyl group, abenzimidazolyl group, a naphthoimidazolyl group, a triazinyl group, animidazopyridinyl group, an imidazopyrimidinyl group, animidazoquinolinyl group, and imidazoisoquinolinyl group, eachsubstituted with at least one selected from deuterium, a C₁-C₂₀ alkylgroup, a phenyl group, a naphthyl group, a fluorenyl group, a carbazolylgroup, a pyridinyl group, —N(Q₄₁)(Q₄₂), and —Si(Q₄₃)(Q₄₄)(Q₄₅); and

a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a quinolinylgroup, an isoquinolinyl group, a benzoquinolinyl group, a naphthyridinylgroup, a quinoxalinyl group, a quinazolinyl group, a phenanthridinylgroup, a phenanthrolinyl group, a benzophenanthrolinyl group, abenzimidazolyl group, a naphthoimidazolyl group, a triazinyl group, animidazopyridinyl group, an imidazopyrimidinyl group, animidazoquinolinyl group, and an imidazoisoquinolinyl group, eachsubstituted with at least one selected from a phenyl group, a naphthylgroup, a fluorenyl group, a carbazolyl group and a pyridinyl group, eachsubstituted with at least one selected from deuterium, a C₁-C₂₀ alkylgroup, a phenyl group, a naphthyl group, a pyridinyl group,—N(Q₅₁)(Q₅₂), and —Si(Q₅₃)(Q₅₄)(Q₅₅);

where Q₄₁ to Q₄₅ and Q₅₁ to Q₅₅ may be each independently selected froma methyl group, an ethyl group, an n-propyl group, an iso-propyl group,an n-butyl group, an iso-butyl group, a sec-butyl group, a tert-butylgroup, a phenyl group, a biphenyl group, a naphthyl group, and afluorenyl group, but embodiments of the present invention are notlimited thereto.

According to some embodiments, R_(ET) in Formula 7 may be selected fromgroups represented by Formulae 6-1 to 6-63 below, but is not limitedthereto:

In Formulae 6-1 to 6-63,

R₆₁ to R₆₃ may be each independently selected from:

deuterium, a C₁-C₂₀ alkyl group, a phenyl group, a naphthyl group, afluorenyl group, a carbazolyl group, a pyridinyl group, —N(Q₄₁)(Q₄₂),and —Si(Q₄₃)(Q₄₄)(Q₄₅); and

a phenyl group, a naphthyl group, a fluorenyl group, a carbazolyl group,a pyridinyl group, each substituted with at least one selected fromdeuterium, a C₁-C₂₀ alkyl group, a phenyl group, a naphthyl group, apyridinyl group, —N(Q₅₁)(Q₅₂), and —Si(Q₅₃)(Q₅₄)(Q₅₅);

where Q₄₁ to Q₄₅ and Q₅₁ to Q₅₅ may be each independently selected froma methyl group, an ethyl group, an n-propyl group, an iso-propyl group,an n-butyl group, an iso-butyl group, a sec-butyl group, a tert-butylgroup, a phenyl group, a biphenyl group, a naphthyl group, and afluorenyl group;

b61 may be selected from 1, 2, 3, and 4; and

b62 may be selected from 1, 2, and 3;

b63 may be selected from 1, 2, 3, 4, 5, and 6;

b64 may be selected from 1, 2, 3, 4, and 5;

b65 may be selected from 1 and 2; and

* indicates a binding site to a neighboring atom.

R₇₂ to R₈₀ in Formula 7 may be each independently selected fromhydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid ora salt thereof, a phosphoric acid or a salt thereof, a substituted orunsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₂-C₆₀alkenyl group, a substituted or unsubstituted C₂-C₆₀ alkynyl group, asubstituted or unsubstituted C₁-C₆₀ alkoxy group, a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group,—N(Q₁)(Q₂), —Si(Q₃)(Q₄)(Q₅), and —B(Q₆)(Q₇);

at least one substituent of the substituted C₁-C₆₀ alkyl group, thesubstituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀ alkynyl group,the substituted C₁-C₆₀ alkoxy group, the substituted C₃-C₁₀ cycloalkylgroup, the substituted C₁-C₁₀ heterocycloalkyl group, the substitutedC₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀ heterocycloalkenylgroup, the substituted C₆-C₆₀ aryl group, the substituted C₆-C₆₀ aryloxygroup, the substituted C₆-C₆₀ arylthio group, the substituted C₁-C₆₀heteroaryl group, the substituted a monovalent non-aromatic condensedpolycyclic group, and the substituted monovalent non-aromatic condensedheteropolycyclic group may be selected from:

deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid group or a salt thereof, a sulfonic acid groupor a salt thereof, a phosphoric acid group or a salt thereof, a C₁-C₆₀alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and aC₁-C₆₀ alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid ora salt thereof, a phosphoric acid or a salt thereof, a C₃-C₁₀ cycloalkylgroup, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, aC₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxygroup, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₁₁)(Q₁₂), —Si(Q₁₃)(Q₁₄)(Q₁₅), and—B(Q₁₆)(Q₁₇);

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, aC₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group,a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₂₁)(Q₂₂), —Si(Q₂₃)(Q₂₄)(Q₂₅), and—B(Q₂₆)(Q₂₇); and

—N(Q₃₁)(Q₃₂), —Si(Q₃₃)(Q₃₄)(Q₃₅), and —B(Q₃₆)(Q₃₇);

where Q₁ to Q₇, Q₁₁ to Q₁₇, Q₂₁ to Q₂₇ and Q₃₁ to Q₃₇ may be eachindependently selected from hydrogen, a C₁-C₆₀ alkyl group, a C₁-C₆₀alkoxy group, a C₆-C₆₀ aryl group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, and a monovalentnon-aromatic condensed heteropolycyclic group.

For example, R₇₂ to R₈₀ in Formula 7 may be each independently selectedfrom:

hydrogen, a methyl group, an ethyl group, an n-propyl group, an n-butylgroup, a phenyl group, a naphthyl group, an anthryl group, a pyrenylgroup, a phenanthrenyl group, a fluorenyl group, a carbazolyl group,—N(Q₁)(Q₂), and —Si(Q₃)(Q₄)(Q₅); and

a phenyl group, a naphthyl group, an anthryl group, a pyrenyl group, aphenanthrenyl group, a fluorenyl group, and a carbazolyl group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a cyano group, a nitro group, a methyl group, a phenyl group, and anaphthyl group,

where Q₁ to Q₅ may be each independently selected from a C₁-C₆₀ alkylgroup, a C₆-C₆₀ aryl group, a monovalent non-aromatic condensedpolycyclic group, and a monovalent non-aromatic condensedheteropolycyclic group, but they are not limited thereto.

In some embodiments, R₇₂ to R₈₀ in Formula 7 may be each independentlyselected from hydrogen, a methyl group, a phenyl group, a naphthylgroup, a carbazolyl group, —N(Q₁)(Q₂), and —Si(Q₃)(Q₄)(Q₅);

where Q₁ to Q₅ may be each independently selected from a methyl group,an ethyl group, a phenyl group, and a naphthyl group, but they are notlimited thereto.

In some embodiments, R₇₂ to R₈₀ in Formula 7 may be each independentlyselected from a phenyl group and a naphthyl group, but are not limitedthereto.

For example, the third compound may be represented by Formula 7-1 below,but is not limited thereto:

In Formula 7-1,

descriptions of L₇₁, a71, R₇₁, R₇₄, and R₇₉ are the same as describedabove.

In some embodiments, the third compound may be selected from Compounds701 to 745 below, but is not limited thereto:

The third compound may have a HOMO energy level of about 5.8 eV to about6.3 eV, and a LUMO energy level of about 2.7 eV to about 3.2 eV.

The third compound may effectively provide and transport electrons intoan emission layer, and substantially block holes from leaking from theemission layer. That is, the third compound may have excellent electrontransport characteristics and hole blocking characteristics.

Accordingly, an organic light-emitting device including the thirdcompound may have a low driving voltage and high efficiency.

In the third compound, an electron transport group may be substituted toa second position on the anthracene moiety. Compared to a compound inwhich an electron transport group is substituted to a ninth position ofthe anthracene moeity, a compound in which an electron transport groupis substituted to the second position of the anthracene moeity may haveexcellent electron transport characteristics and hole blockingcharacteristics. This is further illustrated in Examples and ComparativeExamples described below.

A thickness of the electron transport layer may be in a range of about100 Å to about 1,000 Å, for example, about 150 Å to about 500 Å. Whenthe thickness of the electron transport layer is within any of theranges described above, the electron transport layer may havesatisfactory electron transport characteristics without a substantialincrease in driving voltage.

Also, the electron transport layer may further include, in addition tothe materials described above, a metal-containing material.

The metal-containing material may include a Li complex. The Li complexmay include, for example, Compound ET-D1 (lithium quinolate, LiQ) and/orET-D2.

The electron transport region may include an electron injection layerthat allows electrons to be easily provided from the second electrode190.

The electron injection layer may be formed on the electron transportlayer by using one or more suitable methods, such as vacuum deposition,spin coating casting, a LB method, ink-jet printing, laser-printing,and/or laser-induced thermal imaging. When the electron injection layeris formed by vacuum deposition and/or spin coating, deposition andcoating conditions for the electron injection layer may be the same as(or similar to) those for the hole injection layer.

The electron injection layer may include at least one selected from LiF,NaCl, CsF, Li₂O, BaO, and LiQ.

A thickness of the electron injection layer may be in a range of about 1Å to about 100 Å, for example, about 3 Å to about 90 Å. When thethickness of the electron injection layer is within any of the rangesdescribed above, the electron injection layer may have satisfactoryelectron injection characteristics without a substantial increase indriving voltage.

The second electrode 190 may be positioned on the electron transportregion described above. The second electrode 190 may be a cathode thatis an electron injection electrode, and in this regard, a material forforming the second electrode may be a material having a low workfunction, for example, a metal, an alloy, an electrically conductivecompound, or a mixture thereof. Non-limiting examples of the materialfor forming the second electrode 190 include lithium (Li), magnesium(Mg), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca),magnesium-indium (Mg—In), and magnesium-silver (Mg—Ag). In someembodiments, the material for forming the second electrode 190 may beITO or IZO. The second electrode 190 may be a reflective electrode or atransmissive electrode.

The organic light-emitting device according to embodiments of thepresent invention may be included in a flat panel display deviceincluding a thin film transistor. The thin film transistor may include agate electrode, source and drain electrodes, a gate insulating film, andan active layer, and one of the source and drain electrodes mayelectrically contact the first electrode 110 of the organiclight-emitting device 10. The active layer may include crystallinesilicon, amorphous silicon, organic semiconductor, oxide semiconductor,and/or the like, but embodiments of the present invention are notlimited thereto.

A C₁-C₆₀ alkyl group used herein refers to a linear or branchedaliphatic hydrocarbon monovalent group having 1 to 60 carbon atoms inthe main chain, and non-limiting examples thereof include a methylgroup, an ethyl group, a propyl group, an isobutyl group, a sec-butylgroup, a ter-butyl group, a pentyl group, an iso-amyl group, and a hexylgroup. A C₁-C₆₀ alkylene group used herein refers to a divalent grouphaving the same structure as the C₁-C₆₀ alkyl group.

A C₁-C₆₀ alkoxy group used herein refers to a monovalent grouprepresented by —OA₁₀₁ (where A₁₀₁ is the C₁-C₆₀ alkyl group), andnon-limiting examples thereof include a methoxy group, an ethoxy group,and an isopropyloxy group.

A C₂-C₆₀ alkenyl group used herein refers to a hydrocarbon group havingat least one carbon-carbon double bond at one or more positions along acarbon chain of the C₂-C₆₀ alkyl group (for example, in the middle or ateither terminal end of the C₂-C₆₀ alkyl group), and non-limitingexamples thereof include an ethenyl group, a propenyl group, and abutenyl group. A C₂-C₆₀ alkenylene group used herein refers to adivalent group having the same structure as the C₂-C₆₀ alkenyl group.

A C₂-C₆₀ alkynyl group used herein refers to a hydrocarbon group havingat least one carbon-carbon triple bond at one or more positions along acarbon chain of the C₂-C₆₀ alkyl group (for example, in the middle or ateither terminal end of the C₂-C₆₀ alkyl group), and non-limitingexamples thereof include an ethynyl group and a propynyl group. A C₂-C₆₀alkynylene group used herein refers to a divalent group having the samestructure as the C₂-C₆₀ alkynyl group.

A C₃-C₁₀ cycloalkyl group used herein refers to a monovalent hydrocarbonmonocyclic group having 3 to 10 carbon atoms as ring-forming atoms, andnon-limiting examples thereof include a cyclopropyl group, a cyclobutylgroup, a cyclopentyl group, a cyclohexyl group, and a cycloheptyl group.A C₃-C₁₀ cycloalkylene group used herein refers to a divalent grouphaving the same structure as the C₃-C₁₀ cycloalkyl group.

A C₁-C₁₀ heterocycloalkyl group used herein refers to a monovalentmonocyclic group having at least one hetero atom selected from N, O, P,and S as a ring-forming atom and 1 to 10 carbon atoms as the remainingring-forming atoms, and non-limiting examples thereof include atetrahydrofuranyl group and a tetrahydrothiophenyl group. A C₁-C₁₀heterocycloalkylene group used herein refers to a divalent group havingthe same structure as the C₁-C₁₀ heterocycloalkyl group.

A C₃-C₁₀ cycloalkenyl group used herein refers to a monovalentmonocyclic group that has 3 to 10 carbon atoms as ring-forming atoms andat least one double bond in the ring thereof and does not havearomaticity, and non-limiting examples thereof include a cyclopentenylgroup, a cyclohexenyl group, and a cycloheptenyl group. A C₃-C₁₀cycloalkenylene group used herein refers to a divalent group having thesame structure as the C₃-C₁₀ cycloalkenyl group.

A C₁-C₁₀ heterocycloalkenyl group used herein refers to a monovalentmonocyclic group that has at least one hetero atom selected from N, O,P, and S as a ring-forming atom, 1 to 10 carbon atoms as the remainingring-forming atoms, and at least one double bond in its ring.Non-limiting examples of the C₁-C₁₀ heterocycloalkenyl group include a2,3-hydrofuranyl group and a 2,3-hydrothiophenyl group. A C₁-C₁₀heterocycloalkenylene group used herein refers to a divalent grouphaving the same structure as the C₁-C₁₀ heterocycloalkenyl group.

A C₆-C₆₀ aryl group used herein refers to a monovalent group having acarbocyclic aromatic system having 6 to 60 carbon atoms, and a C₆-C₆₀arylene group used herein refers to a divalent group having acarbocyclic aromatic system having 6 to 60 carbon atoms. Non-limitingexamples of the C₆-C₆₀ aryl group include a phenyl group, a naphthylgroup, an anthracenyl group, a phenanthrenyl group, a pyrenyl group, anda chrysenyl group. When the C₆-C₆₀ aryl group and/or the C₆-C₆₀ arylenegroup include two or more rings, the rings may be fused to each other.

A C₁-C₆₀ heteroaryl group used herein refers to a monovalent grouphaving a carbocyclic aromatic system that includes at least one heteroatom selected from N, O, P, and S as a ring-forming atom, and 1 to 60carbon atoms as the remaining ring-forming atoms. A C₁-C₆₀ heteroarylenegroup used herein refers to a divalent group having a carbocyclicaromatic system that includes at least one hetero atom selected from N,O, P, and S as a ring-forming atom, and 1 to 60 carbon atoms as theremaining ring-forming atoms. Non-limiting examples of the C₁-C₆₀heteroaryl group include a pyridinyl group, a pyrimidinyl group, apyrazinyl group, a pyridazinyl group, a triazinyl group, a quinolinylgroup, and an isoquinolinyl group. When the C₁-C₆₀ heteroaryl groupand/or the C₁-C₆₀ heteroarylene group include two or more rings, therings may be fused to each other.

A C₆-C₆₀ aryloxy group used herein refers to a group represented by—OA₁₀₂ (where A₁₀₂ is the C₆-C₆₀ aryl group), and a C₆-C₆₀ arylthiogroup refers to a group represented by —SA₁₀₃ (where A₁₀₃ is the C₆-C₆₀aryl group).

A monovalent non-aromatic condensed polycyclic group used herein refersto a monovalent group that has two or more rings condensed to eachother, only carbon atoms as ring-forming atoms (for example, 8 to 60carbon atoms), and does not have overall aromaticity. A non-limitingexample of the monovalent non-aromatic condensed polycyclic group is afluorenyl group. A divalent non-aromatic condensed polycyclic group usedherein refers to a divalent group having the same structure as themonovalent non-aromatic condensed polycyclic group.

A monovalent non-aromatic condensed heteropolycyclic group used hereinrefers to a monovalent group that has two or more rings condensed toeach other, has at least one heteroatom selected from N, O P, and S as aring-forming atom, and carbon atoms as the remaining ring-forming atoms(for example, 2 to 60 carbon atoms), and does not have overallaromaticity. A non-limiting example of the monovalent non-aromaticcondensed heteropolycyclic group is a carbazolyl group. A divalentnon-aromatic condensed heteropolycyclic group used herein refers to adivalent group having the same structure as the monovalent non-aromaticcondensed heteropolycyclic group.

The term “Ph” used herein refers to phenyl group, the term “Me” usedherein refers to methyl group, the term “Et” used herein refers to ethylgroup, and the term “ter-Bu” or “But” used herein refers to tert-butyl.

Hereinafter, an organic light-emitting device according to one or moreembodiments of the present invention is described in more detail withreference to Examples. However, these Examples are provided forillustrative purposes only, and should not in any sense be interpretedas limiting the scope of the present disclosure.

EXAMPLES Example 1

An anode was prepared by cutting a glass substrate with ITO/Ag/ITOhaving a thickness of 70 Å/1000 Å/70 Å deposited thereon to a size of 50mm×50 mm×0.4 mm, ultrasonically cleaning the resulting glass substrateby using isopropyl alcohol and pure water, each for 10 minutes, and thenirradiating UV light for 10 minutes thereto and exposing to ozone toclean. Then, the obtained anode was loaded into a vacuum depositionapparatus.

HT13 was deposited on the anode to form a hole injection layer having athickness of 700 Å, and then, HT3 was deposited on the hole injectionlayer to form a hole transport layer having a thickness of 800 Å, andCompound 167B (first compound), 424B (second compound), and CompoundPD82 (dopant) were co-deposited on the hole transport layer at a weightratio of 50:50:10 to form an emission layer having a thickness of 400 Å.

Thereafter, Compound 710 and LiQ were co-deposited on the emission layerat a weight ratio of 5:5 to form an electron transport layer having athickness of 300 Å, and then, LiQ was deposited on the electrontransport layer to form an electron injection layer having a thicknessof 10 Å, and Mg and Ag were co-deposited on the electron injection layerat a weight ratio of 90:10 to form a cathode having a thickness of 120Å, thereby completing manufacture of an organic light-emitting device.

Examples 2 to 8 and Comparative Examples 1 and 6

Organic light-emitting devices were manufactured in the same (orsubstantially the same) manner as in Example 1, except that in formingan emission layer, compounds listed in Table 1 were respectively used.

TABLE 1 First Second Third Weight ratio (first com- com- com-compound:second pound pound pound Dopant compound:dopant) Example 1 167B424B 710 PD82 50:50:10 Example 2 167B 424B 739 PD82 50:50:10 Example 3167B 424B 721 PD82 50:50:10 Example 4 167B 424B 740 PD82 50:50:10Example 5 161A 375A 710 PD82 50:50:10 Example 6 161A 375A 739 PD8250:50:10 Example 7 161A 375A 721 PD82 50:50:10 Example 8 161A 375A 740PD82 50:50:10 Comparative 167B 424B Alq3 PD82 50:50:10 Example 1Comparative 161A 375A Alq3 PD82 50:50:10 Example 2 Comparative A D HPD82 50:50:10 Example 3 Comparative B E H PD82 50:50:10 Example 4Comparative C F I PD82 50:50:10 Example 5 Comparative C G I PD8250:50:10 Example 6

Evaluation Example 1

Driving voltage, current density, luminance, efficiency, color purity,efficiency, and lifespan of the organic light-emitting devices ofExamples 1 to 8 and Comparative Examples 1 to 6 were evaluated by usingKeithley 2400 (Keithley Instruments Inc.), Minolta Cs-1000A (KonicaMinolta, inc.) and PR650 Spectroscan Source Measurement Unit (a productof Photo Research, Inc.). T₉₇ lifespan indicates an amount of time thatelapsed when 100% of the initial luminance of 9000 cd/m² was reduced to97%. Results are shown in Table 2.

TABLE 2 Driving Current First Second Third voltage density EfficiencyT₉₇ compound compound compound Dopant (V) (mA/cm²) (cd/A) (time) Example1 167B 424B 710 PD82 4.3 10.0 88.1 165 Example 2 167B 424B 739 PD82 4.310.0 89.3 147 Example 3 167B 424B 721 PD82 4.4 10.0 86.1 145 Example 4167B 424B 740 PD82 4.2 10.0 91.7 153 Example 5 161A 375A 710 PD82 4.310.0 86.8 156 Example 6 161A 375A 739 PD82 4.3 10.0 87.8 167 Example 7161A 375A 721 PD82 4.4 10.0 85.6 137 Example 8 161A 375A 740 PD82 4.210.0 88.4 143 Comparative 167B 424B Alq3 PD82 5.2 10.0 81.3 85 Example 1Comparative 161A 375A Alq3 PD82 5.0 10.0 79.6 78 Example 2 Comparative AD H PD82 5.6 10.0 65.4 20 Example 3 Comparative B E H PD82 5.8 10.0 61.215 Example 4 Comparative C F I PD82 5.2 10.0 58.5 27 Example 5Comparative C G I PD82 5.4 10.0 60.5 22 Example 6

As illustrated in Table 2, the organic light-emitting devices ofExamples 1 to 8 had significantly better characteristics than theorganic light-emitting devices of Comparative Examples 1 to 6.

Organic light-emitting devices according to embodiments of the presentinvention may have low driving voltage, high efficiency, and longlifespan characteristics.

It should be understood that the exemplary embodiments described thereinshould be considered in a descriptive sense only and not for purposes oflimitation. Descriptions of features or aspects within each embodimentshould typically be considered as available for other similar featuresor aspects in other embodiments.

While one or more embodiments of the present disclosure have beendescribed with reference to the drawing, it will be understood by thoseof ordinary skill in the art that various changes in form and detailsmay be made therein without departing from the spirit and scope of thepresent disclosure as defined by the following claims and equivalentsthereof.

What is claimed is:
 1. An organic light-emitting device comprising: afirst electrode; a second electrode; an organic layer between the firstelectrode and the second electrode, the organic layer comprising anemission layer, and an electron transport region between the emissionlayer and the second electrode, wherein the emission layer comprises afirst compound represented by Formula 1 and a second compoundrepresented by any one of Formulae 2-1 to 2-5; and wherein the electrontransport region comprises a third compound represented by Formula 7:

wherein in Formulae 1, 2-1 to 2-5, and 7, A₁₁, A₁₂, A₁₃, A₁₄, A₂₁, andA₂₂ are each independently selected from a benzene, a naphthalene, apyridine, a pyrimidine, a quinoline, an isoquinoline, a2,6-naphthyridine, a 1,8-naphthyridine, a 1,5-naphthyridine, a1,6-naphthyridine, a 1,7-naphthyridine, a 2,7-naphthyridine, aquinoxaline, a phthalazine, a quinazoline, and a cinnoline; at least oneof A₂₁ and A₂₂ is each independently selected from a quinoline, anisoquinoline, a 2,6-naphthyridine, a 1,8-naphthyridine, a1,5-naphthyridine, a 1,6-naphthyridine, a 1,7-naphthyridine, a2,7-naphthyridine, a quinoxaline, a phthalazine, a quinazoline, and acinnoline; X₁₁ is N[(L₁₂)_(a12)-(R₁₂)_(b12)]; X₂₁ is selected fromN[(L₂₂)_(a22)-(R₂₂)_(b22)] and C[(L₂₂)_(a22)-(R₂₂)_(b22)][R₂₆]; L₁₁ toL₁₃, and L₇₁ are each independently selected from a substituted orunsubstituted C₃-C₁₀ cycloalkylene group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group; L₂₁ and L₂₂ are eachindependently selected from groups represented by Formulae 3-1 to 3-19:

wherein in Formulae 3-1 to 3-19, X₃₁ is selected from O, S, andC(R₃₃)(R₃₄); R₃₁ to R₃₄ are each independently selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a cyano group, a nitro group, a methylgroup, an ethyl group, an n-propyl group, an iso-propyl group, ann-butyl group, iso-butyl group, a sec-butyl group, a tert-butyl group, aphenyl group, and a naphthyl group; b31 is selected from 1, 2, 3, and 4;b32 is selected from 1, 2, 3, 4, 5, and 6; b33 is selected from 1, 2,and 3; and * and *′ each indicate a binding site to a neighboring atom;a11 to a13, a21, a22, and a71 are each independently selected from 0, 1,2, 3, 4, and 5; R₁₁ and R₁₂ are each independently selected from R_(HT)and R_(ET), and at least one selected from R₁₁ and R₁₂ is R_(ET); R₂₁and R₂₂ are each independently R_(HT), provided that when X₂₁ isN[(L₂₂)_(a22)-(R₂₂)_(b22)], R₂₁ and R₂₂ are each independently not asubstituted or unsubstituted furanyl group, carbazolyl group,benzofuranyl group, benzothiophenyl group, dibenzofuranyl group,dibenzothiophenyl group, benzocarbazolyl group, dibenzocarbazolyl group,thianthrenyl group, phenoxathinyl group, or dibenzodioxinyl group, andwhen X₂₁ is C[(L₂₂)_(a22)-(R₂₂)_(b22)][R₂₆], R₂₁ is not a substituted orunsubstituted phenyl group or a substituted or unsubstituted fluorenylgroup; R₇₁ is selected from groups represented by Formulae 6-1 to 6-44and 6-46 to 6-63 below:

wherein in Formulae 6-1 to 6-44 and 6-46 to 6-63, R₆₁ and R₆₂ are eachindependently selected from: deuterium, a C₁-C₂₀ alkyl group, a phenylgroup, a naphthyl group, a fluorenyl group, a carbazolyl group, apyridinyl group, —N(Q₄₁)(Q₄₂), and —Si(Q₄₃)(Q₄₄)(Q₄₅); and a phenylgroup, a naphthyl group, a fluorenyl group, a carbazolyl group, apyridinyl group, each substituted with at least one selected fromdeuterium, a C₁-C₂₀ alkyl group, a phenyl group, a naphthyl group, apyridinyl group, —N(Q₅₁)(Q₅₂), and —Si(Q₅₃)(Q₅₄)(Q₅₅); b61 is selectedfrom 1, 2, 3, and 4; and b62 is selected from 1, 2, and 3; b63 isselected from 1, 2, 3, 4, 5, and 6; b64 is selected from 1, 2, 3, 4, and5; b65 is selected from 1 and 2; and * indicates a binding site to aneighboring atom, wherein Q₄₁ to Q₄₅ and Q₅₁ to Q₅₅ are eachindependently selected from a methyl group, an ethyl group, an n-propylgroup, an iso-propyl group, an n-butyl group, an iso-butyl group, asec-butyl group, a tert-butyl group, a phenyl group, a biphenyl group, anaphthyl group, and a fluorenyl group; b11, b12, b21, and b22 are eachindependently selected from 1, 2, 3, and 4; R₁₃ to R₁₆, R₂₆, and R₇₂ toR₈₀ are each independently selected from hydrogen, deuterium, —F, —Cl,—Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group,an amidino group, a hydrazine group, a hydrazone group, a carboxylicacid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoricacid or a salt thereof, a substituted or unsubstituted C₁-C₆₀ alkylgroup, a substituted or unsubstituted C₂-C₆₀ alkenyl group, asubstituted or unsubstituted C₂-C₆₀ alkynyl group, a substituted orunsubstituted C₁-C₆₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀cycloalkyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkylgroup, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, asubstituted or unsubstituted C₆-C₆₀ aryl group, a substituted orunsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstitutedC₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroarylgroup, a substituted or unsubstituted monovalent non-aromatic condensedpolycyclic group, a substituted or unsubstituted monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₁)(Q₂), —Si(Q₃)(Q₄)(Q₅), and—B(Q₆)(Q₇); R₂₃ to R₂₅ are each independently selected from hydrogen anda phenyl group; b13 to b16 and b23 to b25 are each independentlyselected from 1, 2, 3 and 4; R_(HT) is a hole transport group selectedfrom: a phenyl group, a pentalenyl group, an indenyl group, a naphthylgroup, an azulenyl group, a heptalenyl group, an indacenyl group, anacenaphthyl group, a fluorenyl group, a spiro-fluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, aphenanthrenyl group, an anthracenyl group, a fluoranthenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, athiophenyl group, a furanyl group, a carbazolyl group, a benzofuranylgroup, a benzothiophenyl group, a dibenzofuranyl group, adibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolylgroup, a thianthrenyl group, a phenoxathinyl group, and adibenzodioxinyl group; a phenyl group, a pentalenyl group, an indenylgroup, a naphthyl group, an azulenyl group, a heptalenyl group, anindacenyl group, an acenaphthyl group, a fluorenyl group, aspiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group,a phenalenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a pyrenyl group, a chrysenyl group, a naphthacenylgroup, a picenyl group, a perylenyl group, a pentaphenyl group, ahexacenyl group, a pentacenyl group, a rubicenyl group, a coronenylgroup, an ovalenyl group, a thiophenyl group, a furanyl group, acarbazolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a thianthrenyl group, a phenoxathinylgroup, and a dibenzodioxinyl group, each substituted with at least oneselected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid or a salt thereof, a sulfonic acid or a saltthereof, a phosphoric acid or a salt thereof, a C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a phenyl group, a naphthyl group, a fluorenylgroup, a carbazolyl group, —N(Q₄₁)(Q₄₂), —Si(Q₄₃)(Q₄₄)(Q₄₅), and—B(Q₄₆)(Q₄₇); and a phenyl group, a pentalenyl group, an indenyl group,a naphthyl group, an azulenyl group, a heptalenyl group, an indacenylgroup, an acenaphthyl group, a fluorenyl group, a spiro-fluorenyl group,a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, aphenanthrenyl group, an anthracenyl group, a fluoranthenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, athiophenyl group, a furanyl group, a carbazolyl group, a benzofuranylgroup, a benzothiophenyl group, a dibenzofuranyl group, adibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolylgroup, a thianthrenyl group, a phenoxathinyl group, and adibenzodioxinyl group, each substituted with at least one selected froma phenyl group, a naphthyl group, a fluorenyl group, and a carbazolylgroup, each substituted with at least one selected from deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenylgroup, a naphthyl group, a fluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a carbazolyl group, —N(Q₅₁)(Q₅₂),—Si(Q₅₃)(Q₅₄)(Q₅₅), and —B(Q₅₆)(Q₅₇); R_(ET) is an electron transportgroup selected from: a pyrrolyl group, an imidazolyl group, a pyrazolylgroup, a thiazolyl group, an isothiazolyl group, an oxazolyl group, anisoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, an isoindolyl group, an indolyl group, anindazolyl group, a purinyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinylgroup, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, abenzophenanthrolinyl group, a phenazinyl group, a benzimidazolyl group,a naphthoimidazolyl group, a benzothiazolyl group, an isobenzothiazolylgroup, a benzoxazolyl group, an isobenzoxazolyl group, a triazolylgroup, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, animidazopyridinyl group, an imidazopyrimidinyl group, animidazoquinolinyl group, an imidazoisoquinolinyl group, apyridobenzofuranyl group, a pyrimidobenzofuranyl group, apyridobenzothiophenyl group, and a pyrimidobenzothiophenyl group; apyrrolyl group, an imidazolyl group, a pyrazolyl group, a thiazolylgroup, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, an isoindolyl group, an indolyl group, an indazolyl group, apurinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, abenzophenanthrolinyl group, a phenazinyl group, a benzimidazolyl group,a naphthoimidazolyl group, a benzothiazolyl group, an isobenzothiazolylgroup, a benzoxazolyl group, an isobenzoxazolyl group, a triazolylgroup, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, animidazopyridinyl group, an imidazopyrimidinyl group, animidazoquinolinyl group, an imidazoisoquinolinyl group, apyridobenzofuranyl group, a pyrimidobenzofuranyl group, apyridobenzothiophenyl group, and a pyrimidobenzothiophenyl group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a naphthylgroup, a fluorenyl group, a carbazolyl group, a pyridinyl group, apyrimidinyl group, a triazinyl group, —N(Q₄₁)(Q₄₂), —Si(Q₄₃)(Q₄₄)(Q₄₅),and —B(Q₄₆)(Q₄₇); and a pyrrolyl group, an imidazolyl group, a pyrazolylgroup, a thiazolyl group, an isothiazolyl group, an oxazolyl group, anisoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, an isoindolyl group, an indolyl group, anindazolyl group, a purinyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinylgroup, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, abenzophenanthrolinyl group, a phenazinyl group, a benzimidazolyl group,a naphthoimidazolyl group, a benzothiazolyl group, an isobenzothiazolylgroup, a benzoxazolyl group, an isobenzoxazolyl group, a triazolylgroup, a tetrazolyl group, an oxadiazolyl group, a triazinyl group, animidazopyridinyl group, an imidazopyrimidinyl group, animidazoquinolinyl group, an imidazoisoquinolinyl group, apyridobenzofuranyl group, a pyrimidobenzofuranyl group, apyridobenzothiophenyl group, and a pyrimidobenzothiophenyl group, eachsubstituted with at least one selected from a phenyl group, a naphthylgroup, a fluorenyl group, a carbazolyl group, a pyridinyl group, apyrimidinyl group, and a triazinyl group, each substituted with at leastone selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid or a salt thereof, a sulfonic acid or a saltthereof, a phosphoric acid or a salt thereof, a C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a phenyl group, a naphthyl group, a fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a carbazolylgroup, a pyridinyl group, a pyrimidinyl group, a triazinyl group,—N(Q₅₁)(Q₅₂), —Si(Q₅₃)(Q₅₄)(Q₅₅), and —B(Q₅₆)(Q₅₇); and at least onesubstituent of the substituted C₃-C₁₀ cycloalkylene group, thesubstituted C₁-C₁₀ heterocycloalkylene group, the substituted C₃-C₁₀cycloalkenylene group, the substituted C₁-C₁₀ heterocycloalkenylenegroup, the substituted C₆-C₆₀ arylene group, the substituted C₁-C₆₀heteroarylene group, the substituted divalent non-aromatic condensedpolycyclic group, the substituted divalent non-aromatic condensedheteropolycyclic group, the substituted C₁-C₆₀ alkyl group, thesubstituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀ alkynyl group,the substituted C₁-C₆₀ alkoxy group, the substituted C₃-C₁₀ cycloalkylgroup, the substituted C₁-C₁₀ heterocycloalkyl group, the substitutedC₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀ heterocycloalkenylgroup, the substituted C₆-C₆₀ aryl group, the substituted C₆-C₆₀ aryloxygroup, the substituted C₆-C₆₀ arylthio group, the substituted C₁-C₆₀heteroaryl group, the substituted monovalent non-aromatic condensedpolycyclic group, and the substituted monovalent non-aromatic condensedheteropolycyclic group is selected from: deuterium, —F, —Cl, —Br, —I, ahydroxyl group, a cyano group, a nitro group, an amino group, an amidinogroup, a hydrazine group, a hydrazone group, a carboxylic acid group ora salt thereof, a sulfonic acid group or a salt thereof, a phosphoricacid group or a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenylgroup, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group; a C₁-C₆₀ alkylgroup, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀alkoxy group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid or a salt thereof, a sulfonic acid or a saltthereof, a phosphoric acid or a salt thereof, a C₃-C₁₀ cycloalkyl group,a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₁₁)(C₁₂), —Si(Q₁₃)(Q₁₄)(Q₁₅), and—B(Q₁₆)(Q₁₇); a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkylgroup, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup, and a monovalent non-aromatic condensed heteropolycyclic group; aC₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, aC₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group,a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₂₁)(Q₂₂), —Si(Q₂₃)(Q₂₄)(Q₂₅), and—B(Q₂₆)(Q₂₇); and —N(Q₃₁)(Q₃₂), —Si(Q₃₃)(Q₃₄)(Q₃₅), and —B(Q₃₆)(Q₃₇);wherein Q₁ to Q₇, Q₁₁ to Q₁₇, Q₂₁ to Q₂₇ and Q₃₁ to Q₃₇ are eachindependently selected from hydrogen, a C₁-C₆₀ alkyl group, a C₁-C₆₀alkoxy group, a C₆-C₆₀ aryl group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, and a monovalentnon-aromatic condensed heteropolycyclic group, and wherein Q₄₁ to Q₄₇and Q₅₁ to Q₅₇ are each independently selected from a C₁-C₆₀ alkylgroup, a C₆-C₆₀ aryl group, a monovalent non-aromatic condensedpolycyclic group, and a monovalent non-aromatic condensedheteropolycyclic group.
 2. The organic light-emitting device of claim 1,wherein neither the first compound nor the second compound comprises acyano group.
 3. The organic light-emitting device of claim 1, whereinL₁₁ to L₁₃, and L₇₁ are each independently selected from groupsrepresented by Formulae 3-1 to 3-19:

wherein in Formulae 3-1 to 3-19, X₃₁ is selected from O, S, andC(R₃₃)(R₃₄); R₃₁ to R₃₄ are each independently selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a cyano group, a nitro group, a methylgroup, an ethyl group, an n-propyl group, an iso-propyl group, ann-butyl group, iso-butyl group, a sec-butyl group, a tert-butyl group, aphenyl group, and a naphthyl group; b31 is selected from 1, 2, 3, and 4;b32 is selected from 1, 2, 3, 4, 5, and 6; b33 is selected from 1, 2,and 3; and * and *′ each indicate a binding site to a neighboring atom.4. The organic light-emitting device of claim 1, wherein R_(HT) isselected from groups represented by Formulae 5-1 to 5-10 below:

wherein in Formulae 5-1 to 5-10, X₅₁ is selected from a single bond,N(R₅₄), C(R₅₄)(R₅₅), O, and S; X₅₂ is selected from N(R₅₆), C(R₅₆)(R₅₇),O, and S; R₅₁, R₅₂ and R₅₄ to R₅₇ are each independently selected from:deuterium, a C₁-C₂₀ alkyl group, a phenyl group, a naphthyl group, afluorenyl group, a carbazolyl group, —N(Q₄₁)(Q₄₂), and—Si(Q₄₃)(Q₄₄)(Q₄₅); and a phenyl group, a naphthyl group, a fluorenylgroup, and a carbazolyl group, each substituted with at least oneselected from deuterium, a C₁-C₂₀ alkyl group, a phenyl group, anaphthyl group, —N(Q₅₁)(Q₅₂), and —Si(Q₅₃)(Q₅₄)(Q₅₅); wherein Q₄₁ to Q₄₅and Q₅₁ to Q₅₅ are each independently selected from a methyl group, anethyl group, an n-propyl group, an iso-propyl group, an n-butyl group,an iso-butyl group, a sec-butyl group, a tert-butyl group, a phenylgroup, a biphenyl group, a naphthyl group, and a fluorenyl group; b51 isselected from 1, 2, 3, 4, and 5; b52 is selected from 1, 2, 3, 4, 5, 6,and 7; b53 is selected from 1, 2, and 3; b54 is selected from 1, 2, 3,and 4; b55 is selected from 1, 2, 3, 4, 5, and 6; and * indicates abinding site to a neighboring atom.
 5. The organic light-emitting deviceof claim 1, wherein R_(ET) is selected from groups represented byFormulae 6-1 to 6-63 below:

wherein in Formulae 6-1 to 6-63, R₆₁ to R₆₃ are each independentlyselected from: deuterium, a C₁-C₂₀ alkyl group, a phenyl group, anaphthyl group, a fluorenyl group, a carbazolyl group, a pyridinylgroup, —N(Q₄₁)(Q₄₂), and —Si(Q₄₃)(Q₄₄)(Q₄₅); and a phenyl group, anaphthyl group, a fluorenyl group, a carbazolyl group, a pyridinylgroup, each substituted with at least one selected from deuterium, aC₁-C₂₀ alkyl group, a phenyl group, a naphthyl group, a pyridinyl group,—N(Q₅₁)(Q₅₂), and —Si(Q₅₃)(Q₅₄)(Q₅₅); b61 is selected from 1, 2, 3, and4; and b62 is selected from 1, 2, and 3; b63 is selected from 1, 2, 3,4, 5, and 6; b64 is selected from 1, 2, 3, 4, and 5; b65 is selectedfrom 1 and 2; and * indicates a binding site to a neighboring atom,wherein Q₄₁ to Q₄₅ and Q₅₁ to Q₅₅ are each independently selected from amethyl group, an ethyl group, an n-propyl group, an iso-propyl group, ann-butyl group, an iso-butyl group, a sec-butyl group, a tert-butylgroup, a phenyl group, a biphenyl group, a naphthyl group, and afluorenyl group.
 6. The organic light-emitting device of claim 1,wherein the first compound is represented by Formula 1-1 below:


7. The organic light-emitting device of claim 1, wherein the secondcompound is represented by any one of Formulae 2-11 to 2-15 below:


8. The organic light-emitting device of claim 1, wherein the thirdcompound is represented by Formula 7-1 below:


9. An organic light-emitting device comprising: a first electrode; asecond electrode; an organic layer between the first electrode and thesecond electrode, the organic layer comprising an emission layer, and anelectron transport region between the emission layer and the secondelectrode, wherein the emission layer comprises a first compoundrepresented by Formula 1 and a second compound represented by one ofFormulae 2-1 to 2-5; and wherein the electron transport region comprisesa third compound represented by Formula 7:

wherein in Formulae 1, 2-1 to 2-5, and 7, A₁₁, A₁₂, A₁₃, A₁₄, A₂₁, andA₂₂ are each independently selected from a benzene, a naphthalene, apyridine, a pyrimidine, a quinoline, an isoquinoline, a2,6-naphthyridine, a 1,8-naphthyridine, a 1,5-naphthyridine, a1,6-naphthyridine, a 1,7-naphthyridine, a 2,7-naphthyridine, aquinoxaline, a phthalazine, a quinazoline, and a cinnoline; at least oneof A₂₁ and A₂₂ is each independently selected from a quinoline, anisoquinoline, a 2,6-naphthyridine, a 1,8-naphthyridine, a1,5-naphthyridine, a 1,6-naphthyridine, a 1,7-naphthyridine, a2,7-naphthyridine, a quinoxaline, a phthalazine, a quinazoline, and acinnoline; X₁₁ is N[(L₁₂)_(a12)-(R₁₂)_(b12)]; X₂₁ is selected from O, S,N[(L₂₂)_(a22)-(R₂₂)_(b22)], and C[(L₂₂)_(a22)-(R₂₂)_(b22)][R₂₆]; L₁₁ andL₁₂ are each independently selected from groups represented by Formulae3-1 to 3-19:

wherein in Formulae 3-1 to 3-19, X₃₁ is selected from O, S, andC(R₃₃)(R₃₄); R₃₁ to R₃₄ are each independently selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a cyano group, a nitro group, a methylgroup, an ethyl group, an n-propyl group, an iso-propyl group, ann-butyl group, iso-butyl group, a sec-butyl group, a tert-butyl group, aphenyl group, and a naphthyl group; b31 is selected from 1, 2, 3, and 4;b32 is selected from 1, 2, 3, 4, 5, and 6; b33 is selected from 1, 2,and 3; and * and *′ each indicate a binding site to a neighboring atom;L₁₃, L₂₁, L₂₂, and L₇₁ are each independently selected from asubstituted or unsubstituted C₃-C₁₀ cycloalkylene group, a substitutedor unsubstituted C₁-C₁₀ heterocycloalkylene group, a substituted orunsubstituted C₃-C₁₀ cycloalkenylene group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenylene group, a substituted orunsubstituted C₆-C₆₀ arylene group, a substituted or unsubstitutedC₁-C₆₀ heteroarylene group, a substituted or unsubstituted divalentnon-aromatic condensed polycyclic group, and a substituted orunsubstituted divalent non-aromatic condensed heteropolycyclic group;a11 to a13, a21, a22, and a71 are each independently selected from 0, 1,2, 3, 4, and 5; R₁₁ and R₁₂ are each independently R_(HT); R₂₁ and R₂₂are each independently selected from R_(HT) and R_(ET), and at least oneselected from R₂₁ and R₂₂ is R_(ET); R₇₁ is selected from groupsrepresented by Formulae 6-4 to 6-39 below:

wherein in Formulae 6-4 to 6-39, R₆₁ and R₆₂ are each independentlyselected from: deuterium, a C₁-C₂₀ alkyl group, a phenyl group, anaphthyl group, a fluorenyl group, a carbazolyl group, a pyridinylgroup, —N(Q₄₁)(Q₄₂), and —Si(Q₄₃)(Q₄₄)(Q₄₅); and a phenyl group, anaphthyl group, a fluorenyl group, a carbazolyl group, a pyridinylgroup, each substituted with at least one selected from deuterium, aC₁-C₂₀ alkyl group, a phenyl group, a naphthyl group, a pyridinyl group,—N(Q₅₁)(Q₅₂), and —Si(Q₅₃)(Q₅₄)(Q₅₅), b62 is selected from 1, 2, and 3;b63 is selected from 1, 2, 3, 4, 5, and 6; b64 is selected from 1, 2, 3,4, and 5; and * indicates a binding site to a neighboring atom, whereinQ₄₁ to Q₄₅ and Q₅₁ to Q₅₅ are each independently selected from a methylgroup, an ethyl group, an n-propyl group, an iso-propyl group, ann-butyl group, an iso-butyl group, a sec-butyl group, a tert-butylgroup, a phenyl group, a biphenyl group, a naphthyl group, and afluorenyl group; b11, b12, b21, and b22 are each independently selectedfrom 1, 2, 3, and 4; R₁₃ to R₁₆, R₂₃ to R₂₅, and R₇₂ to R₈₀ are eachindependently hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a substituted or unsubstituted C₁-C₆₀ alkyl group, a substituted orunsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstitutedC₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxygroup, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, asubstituted or unsubstituted heterocycloalkyl group, a substituted orunsubstituted C₃-C₁₀ cycloalkenyl group, a substituted or unsubstitutedheterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstituted amonovalent non-aromatic condensed polycyclic group, and a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group;b13 to b16 and b23 to b25 are each independently selected from 1, 2, 3and 4; R_(HT) is a hole transport group selected from: a phenyl group, apentalenyl group, an indenyl group, a naphthyl group, an azulenyl group,a heptalenyl group, an indacenyl group, an acenaphthyl group, afluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, athiophenyl group, a furanyl group, a carbazolyl group, a benzofuranylgroup, a benzothiophenyl group, a dibenzofuranyl group, adibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolylgroup, a thianthrenyl group, a phenoxathinyl group, and adibenzodioxinyl group; a phenyl group, a pentalenyl group, an indenylgroup, a naphthyl group, an azulenyl group, a heptalenyl group, anindacenyl group, an acenaphthyl group, a fluorenyl group, aspiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group,a phenalenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a naphthacenyl group, a picenyl group, a perylenyl group, apentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenylgroup, a coronenyl group, an ovalenyl group, a thiophenyl group, afuranyl group, a carbazolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, athianthrenyl group, a phenoxathinyl group, and a dibenzodioxinyl group,each substituted with at least one selected from deuterium, —F, —Cl,—Br, —I, a hydroxyl group, a nitro group, an amino group, an amidinogroup, a hydrazine group, a hydrazone group, a carboxylic acid or a saltthereof, a sulfonic acid or a salt thereof, a phosphoric acid or a saltthereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, anaphthyl group, a fluorenyl group, a carbazolyl group, —N(Q₄₁)(Q₄₂),—Si(Q₄₃)(Q₄₄)(Q₄₅), and —B(Q₄₆)(Q₄₇); and a phenyl group, a pentalenylgroup, an indenyl group, a naphthyl group, an azulenyl group, aheptalenyl group, an indacenyl group, an acenaphthyl group, a fluorenylgroup, a spiro-fluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, athiophenyl group, a furanyl group, a carbazolyl group, a benzofuranylgroup, a benzothiophenyl group, a dibenzofuranyl group, adibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolylgroup, a thianthrenyl group, a phenoxathinyl group, and adibenzodioxinyl group, each substituted with at least one selected froma phenyl group, a naphthyl group, a fluorenyl group, and a carbazolylgroup, each substituted with at least one selected from deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenylgroup, a naphthyl group, a fluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a carbazolyl group, —N(Q₅₁)(Q₅₂),—Si(Q₅₃)(Q₅₄)(Q₅₅), and —B(Q₅₆)(Q₅₇); R_(ET) is an electron transportgroup selected from: a pyrrolyl group, an imidazolyl group, a pyrazolylgroup, a thiazolyl group, an isothiazolyl group, an oxazolyl group, anisoxazolyl group, a pyridazinyl group, an isoindolyl group, an indolylgroup, an indazolyl group, a purinyl group, a quinolinyl group, anisoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, anaphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, acinnolinyl group, a phenanthridinyl group, an acridinyl group, aphenanthrolinyl group, a benzophenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, a naphthoimidazolyl group, a benzothiazolylgroup, an isobenzathiazolyl group, a benzoxazolyl group, anisobenzoxazolyl group, a triazolyl group, a tetrazolyl group, anoxadiazolyl group, an imidazopyridinyl group, an imidazopyrimidinylgroup, an imidazoquinolinyl group, an imidazoisoquinolinyl group, apyridobenzofuranyl group, a pyrimidobenzofuranyl group, apyridobenzothiophenyl group, and a pyrimidobenzothiophenyl group; apyrrolyl group, an imidazolyl group, a pyrazolyl group, a thiazolylgroup, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, apyridazinyl group, an isoindolyl group, an indolyl group, an indazolylgroup, a purinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, abenzophenanthrolinyl group, a phenazinyl group, a benzimidazolyl group,a naphthoimidazolyl group, a benzothiazolyl group, an isobenzothiazolylgroup, a benzoxazolyl group, an isobenzoxazolyl group, a triazolylgroup, a tetrazolyl group, an oxadiazolyl group, an imidazopyridinylgroup, an imidazopyrimidinyl group, an imidazoquinolinyl group, animidazoisoquinolinyl group, a pyridobenzofuranyl group, apyrimidobenzofuranyl group, a pyridobenzothiophenyl group, and apyrimidobenzothiophenyl group, each substituted with at least oneselected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid or a salt thereof, a sulfonic acid or a saltthereof, a phosphoric acid or a salt thereof, a C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a phenyl group, a naphthyl group, a fluorenylgroup, a carbazolyl group, —N(Q₄₁)(Q₄₂), —Si(Q₄₃)(Q₄₄)(Q₄₅), and—B(Q₄₆)(Q₄₇); and a pyrrolyl group, an imidazolyl group, a pyrazolylgroup, a thiazolyl group, an isothiazolyl group, an oxazolyl group, anisoxazolyl group, a pyridazinyl group, an isoindolyl group, an indolylgroup, an indazolyl group, a purinyl group, a quinolinyl group, anisoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, anaphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, acinnolinyl group, a phenanthridinyl group, an acridinyl group, aphenanthrolinyl group, a benzophenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, a naphthoimidazolyl group, a benzothiazolylgroup, an isobenzothiazolyl group, a benzoxazolyl group, anisobenzoxazolyl group, a triazolyl group, a tetrazolyl group, anoxadiazolyl group, an imidazopyridinyl group, an imidazopyrimidinylgroup, an imidazoquinolinyl group, an imidazoisoquinolinyl group, apyridobenzofuranyl group, a pyrimidobenzofuranyl group, apyridobenzothiophenyl group, and a pyrimidobenzothiophenyl group, eachsubstituted with at least one selected from a phenyl group, a naphthylgroup, a fluorenyl group, and a carbazolyl group, each substituted withat least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid or a salt thereof, asulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, aC₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a naphthylgroup, a fluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a carbazolyl group, —N(Q₅₁)(Q₅₂), —Si(Q₅₃)(Q₅₄)(Q₅₅), and—B(Q₅₆)(Q₅₇); and at least one substituent of the substituted C₃-C₁₀cycloalkylene group, the substituted C₁-C₁₀ heterocycloalkylene group,the substituted C₃-C₁₀ cycloalkenylene group, the substituted C₁-C₁₀heterocycloalkenylene group, the substituted C₆-C₆₀ arylene group, thesubstituted C₁-C₆₀ heteroarylene group, the substituted divalentnon-aromatic condensed polycyclic group, the substituted divalentnon-aromatic condensed heteropolycyclic group, the substituted C₁-C₆₀alkyl group, the substituted C₂-C₆₀ alkenyl group, the substitutedC₂-C₆₀ alkynyl group, the substituted C₁-C₆₀ alkoxy group, thesubstituted C₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀heterocycloalkyl group, the substituted C₃-C₁₀ cycloalkenyl group, thesubstituted C₁-C₁₀ heterocycloalkenyl group, the substituted C₆-C₆₀ arylgroup, the substituted C₆-C₆₀ aryloxy group, the substituted C₆-C₆₀arylthio group, the substituted C₁-C₆₀ heteroaryl group, the substitutedmonovalent non-aromatic condensed polycyclic group, and the substitutedmonovalent non-aromatic condensed heteropolycyclic group is selectedfrom: deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid group or a salt thereof, a sulfonicacid group or a salt thereof, a phosphoric acid group or a salt thereof,a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group; a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group,a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group, each substituted withat least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group,—N(Q₁₁)(Q₁₂), —Si(Q₁₃)(Q₁₄)(Q₁₅), and —B(Q₁₆)(Q₁₇); a C₃-C₁₀ cycloalkylgroup, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, aC₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxygroup, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, and a monovalent non-aromaticcondensed heteropolycyclic group; a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, and a monovalent non-aromaticcondensed heteropolycyclic group, each substituted with at least oneselected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid or a salt thereof, asulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, aC₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, aC₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₂₁)(Q₂₂), —Si(Q₂₃)(Q₂₄)(Q₂₅), and—B(Q₂₆)(Q₂₇); and —N(Q₃₁)(Q₃₂), —Si(Q₃₃)(Q₃₄)(Q₃₅), and —B(Q₃₆)(Q₃₇);wherein Q₁₁ to Q₁₇, Q₂₁ to Q₂₇, and Q₃₁ to Q₃₇ are each independentlyselected from hydrogen, a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkoxy group, aC₆-C₆₀ aryl group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromaticcondensed polycyclic group, and a monovalent non-aromatic condensedheteropolycyclic group, and wherein Q₄₁ to Q₄₇ and Q₅₁ to Q₅₇ are eachindependently selected from a C₁-C₆₀ alkyl group, a C₆-C₆₀ aryl group, amonovalent non-aromatic condensed polycyclic group, and a monovalentnon-aromatic condensed heteropolycyclic group.
 10. The organiclight-emitting device of claim 9, wherein neither the first compound northe second compound comprises a cyano group.
 11. The organiclight-emitting device of claim 9, wherein L₁₃, L₂₁, L₂₂, and L₇₁ areeach independently selected from groups represented by Formulae 3-1 to3-19:

wherein in Formulae 3-1 to 3-19, X₃₁ is selected from O, S, andC(R₃₃)(R₃₄); R₃₁ to R₃₄ are each independently selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a cyano group, a nitro group, a methylgroup, an ethyl group, an n-propyl group, an iso-propyl group, ann-butyl group, iso-butyl group, a sec-butyl group, a tert-butyl group, aphenyl group, and a naphthyl group; b31 is selected from 1, 2, 3, and 4;b32 is selected from 1, 2, 3, 4, 5, and 6; b33 is selected from 1, 2,and 3; and * and *′ each indicate a binding site to a neighboring atom.12. The organic light-emitting device of claim 9, wherein R_(HT) isselected from groups represented by Formulae 5-1 to 5-12 below:

wherein in Formulae 5-1 to 5-12, X₅₁ is selected from a single bond,N(R₅₄), C(R₅₄)(R₅₅), O, and S; X₅₂ is selected from N(R₅₆), C(R₅₆)(R₅₇),O, and S; R₅₁ to R₅₇ are each independently selected from: deuterium, aC₁-C₂₀ alkyl group, a phenyl group, a naphthyl group, a fluorenyl group,a carbazolyl group, —N(Q₄₁)(Q₄₂), and —Si(Q₄₃)(Q₄₄)(Q₄₅); and a phenylgroup, a naphthyl group, a fluorenyl group, and a carbazolyl group, eachsubstituted with at least one selected from deuterium, a C₁-C₂₀ alkylgroup, a phenyl group, a naphthyl group, —N(Q₅₁)(Q₅₂), and—Si(Q₅₃)(Q₅₄)(Q₅₅); wherein Q₄₁ to Q₄₅ and Q₅₁ to Q₅₅ are eachindependently selected from a methyl group, an ethyl group, an n-propylgroup, an iso-propyl group, an n-butyl group, an iso-butyl group, asec-butyl group, a tert-butyl group, a phenyl group, a biphenyl group, anaphthyl group, and a fluorenyl group; b51 is selected from 1, 2, 3, 4,and 5; b52 is selected from 1, 2, 3, 4, 5, 6, and 7; b53 is selectedfrom 1, 2, and 3; b54 is selected from 1, 2, 3, and 4; b55 is selectedfrom 1, 2, 3, 4, 5, and 6; and * indicates a binding site to aneighboring atom.
 13. The organic light-emitting device of claim 9,wherein R_(ET) is selected from groups represented by Formulae 6-10 to6-63 below:

wherein in Formulae 6-10 to 6-63, R₆₁ to R₆₃ are each independentlyselected from: deuterium, a C₁-C₂₀ alkyl group, a phenyl group, anaphthyl group, a fluorenyl group, a carbazolyl group, a pyridinylgroup, —N(Q₄₁)(Q₄₂), and —Si(Q₄₃)(Q₄₄)(Q₄₅); and a phenyl group, anaphthyl group, a fluorenyl group, a carbazolyl group, a pyridinylgroup, each substituted with at least one selected from deuterium, aC₁-C₂₀ alkyl group, a phenyl group, a naphthyl group, a pyridinyl group,—N(Q₅₁)(Q₅₂), and —Si(Q₅₃)(Q₅₄)(Q₅₅), b61 is selected from 1, 2, 3, and4; and b62 is selected from 1, 2, and 3; b63 is selected from 1, 2, 3,4, 5, and 6; b64 is selected from 1, 2, 3, 4, and 5; b65 is selectedfrom 1 and 2; and * indicates a binding site to a neighboring atom,wherein Q₄₁ to Q₄₅ and Q₅₁ to Q₅₅ are each independently selected from amethyl group, an ethyl group, an n-propyl group, an iso-propyl group, ann-butyl group, an iso-butyl group, a sec-butyl group, a tert-butylgroup, a phenyl group, a biphenyl group, a naphthyl group, and afluorenyl group.
 14. The organic light-emitting device of claim 9,wherein the first compound is represented by Formula 1-1 below:


15. The organic light-emitting device of claim 9, wherein the secondcompound is represented by any one of Formulae 2-11 to 2-15 below:


16. The organic light-emitting device of claim 9, wherein the thirdcompound is represented by Formula 7-1 below:


17. An organic light-emitting device comprising: a first electrode; asecond electrode; an organic layer between the first electrode and thesecond electrode, the organic layer comprising an emission layer, and anelectron transport region between the emission layer and the secondelectrode, wherein the emission layer comprises a first compoundrepresented by Formula 1 and a second compound represented by any one ofFormulae 2-1 to 2-5; and wherein the electron transport region comprisesa third compound represented by Formula 7:

wherein in Formulae 1, 2-1 to 2-5, and 7, A₁₁, A₁₂, A₁₃, A₁₄, A₂₁, andA₂₂ are each independently selected from a benzene, a naphthalene, apyridine, a pyrimidine, a quinoline, an isoquinoline, a2,6-naphthyridine, a 1,8-naphthyridine, a 1,5-naphthyridine, a1,6-naphthyridine, a 1,7-naphthyridine, a 2,7-naphthyridine, aquinoxaline, a phthalazine, a quinazoline, and a cinnoline; X₁₁ isselected from O, S, N[(L₁₂)_(a12)-(R₁₂)_(b12)],C[(L₁₂)_(a12)-(R₁₂)_(b12)][R₁₇], Si[(L₁₂)_(a12)-(R₁₂)_(b12)][R₁₇],P[(L₁₂)_(a12)-(R₁₂)_(b12)], B[(L₁₂)_(a12)-(R₁₂)_(b12)], andP(═O)[(L₁₂)_(a12)-(R₁₂)_(b12)]; X₂₁ is selected fromSi[(L₂₂)_(a22)-(R₂₂)_(b22)][R₂₆], P[(L₂₂)_(a22)-(R₂₂)_(b22)],B[(L₂₂)_(a22)-(R₂₂)_(b22)], and P(═O)[(L₂₂)_(a22)-(R₂₂)_(b22)]; L₁₁ toL₁₃, L₂₁, L₂₂, and L₇₁ are each independently selected from asubstituted or unsubstituted C₃-C₁₀ cycloalkylene group, a substitutedor unsubstituted C₁-C₁₀ heterocycloalkylene group, a substituted orunsubstituted C₃-C₁₀ cycloalkenylene group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenylene group, a substituted orunsubstituted C₆-C₆₀ arylene group, a substituted or unsubstitutedC₁-C₆₀ heteroarylene group, a substituted or unsubstituted divalentnon-aromatic condensed polycyclic group, and a substituted orunsubstituted divalent non-aromatic condensed heteropolycyclic group;a11 to a13, a21, a22, and a71 are each independently selected from 0, 1,2, 3, 4, and 5; R₁₁ and R₁₂ are each independently selected from R_(HT)and R_(ET), and at least one selected from R₁₁ and R₁₂ is R_(ET); R₂₁and R₂₂ are each independently R_(HT); R₇₁ is R_(ET); b11, b12, b21, andb22 are each independently selected from 1, 2, 3, and 4; R₁₃ to R₁₇, R₂₃to R₂₆, and R₇₂ to R₈₀ are each independently selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid or a salt thereof, a sulfonic acid or a saltthereof, a phosphoric acid or a salt thereof, a substituted orunsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₂-C₆₀alkenyl group, a substituted or unsubstituted C₂-C₆₀ alkynyl group, asubstituted or unsubstituted C₁-C₆₀ alkoxy group, a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group,—N(Q₁)(Q₂), —Si(Q₃)(Q₄)(Q₅), and —B(Q₆)(Q₇); b13 to b16 and b23 to b25are each independently selected from 1, 2, 3 and 4; R_(HT) is a holetransport group; R_(ET) is an electron transport group; and at least onesubstituent of the substituted C₃-C₁₀ cycloalkylene group, thesubstituted C₁-C₁₀ heterocycloalkylene group, the substituted C₃-C₁₀cycloalkenylene group, the substituted C₁-C₁₀ heterocycloalkenylenegroup, the substituted C₆-C₆₀ arylene group, the substituted C₁-C₆₀heteroarylene group, the substituted divalent non-aromatic condensedpolycyclic group, the substituted divalent non-aromatic condensedheteropolycyclic group, the substituted C₁-C₆₀ alkyl group, thesubstituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀ alkynyl group,the substituted C₁-C₆₀ alkoxy group, the substituted C₃-C₁₀ cycloalkylgroup, the substituted C₁-C₁₀ heterocycloalkyl group, the substitutedC₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀ heterocycloalkenylgroup, the substituted C₆-C₆₀ aryl group, the substituted C₆-C₆₀ aryloxygroup, the substituted C₆-C₆₀ arylthio group, the substituted C₁-C₆₀heteroaryl group, the substituted monovalent non-aromatic condensedpolycyclic group, and the substituted monovalent non-aromatic condensedheteropolycyclic group is selected from: deuterium, —F, —Cl, —Br, —I, ahydroxyl group, a cyano group, a nitro group, an amino group, an amidinogroup, a hydrazine group, a hydrazone group, a carboxylic acid group ora salt thereof, a sulfonic acid group or a salt thereof, a phosphoricacid group or a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenylgroup, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group; a C₁-C₆₀ alkylgroup, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀alkoxy group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid or a salt thereof, a sulfonic acid or a saltthereof, a phosphoric acid or a salt thereof, a C₃-C₁₀ cycloalkyl group,a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₁₁)(Q₁₂), —Si(Q₁₃)(Q₁₄)(Q₁₅), and—B(Q₁₆)(Q₁₇); a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkylgroup, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup, and a monovalent non-aromatic condensed heteropolycyclic group; aC₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, aC₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group,a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₂₁)(Q₂₂), —Si(Q₂₃)(Q₂₄)(Q₂₅), and—B(Q₂₆)(Q₂₇); and —N(Q₃₁)(Q₃₂), —Si(Q₃₃)(Q₃₄)(Q₃₅), and —B(Q₃₆)(Q₃₇);wherein Q₁ to Q₇, Q₁₁ to Q₁₇, Q₂₁ to Q₂₇ and Q₃₁ to Q₃₇ are eachindependently selected from hydrogen, a C₁-C₆₀ alkyl group, a C₁-C₆₀alkoxy group, a C₆-C₆₀ aryl group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, and a monovalentnon-aromatic condensed heteropolycyclic group.
 18. An organiclight-emitting device comprising: a first electrode; a second electrode;an organic layer between the first electrode and the second electrode,the organic layer comprising an emission layer, and an electrontransport region between the emission layer and the second electrode,wherein the emission layer comprises a first compound represented byFormula 1 and a second compound represented by one of Formulae 2-1 to2-5; and wherein the electron transport region comprises a thirdcompound represented by Formula 7:

wherein in Formulae 1, 2-1 to 2-5, and 7, A₁₁, A₁₂, A₁₃, A₁₄, A₂₁, andA₂₂ are each independently selected from a benzene, a naphthalene, apyridine, a pyrimidine, a quinoline, an isoquinoline, a2,6-naphthyridine, a 1,8-naphthyridine, a 1,5-naphthyridine, a1,6-naphthyridine, a 1,7-naphthyridine, a 2,7-naphthyridine, aquinoxaline, a phthalazine, a quinazoline, and a cinnoline; X₁₁ isselected from O, S, N[(L₁₂)_(a12)-(R₁₂)_(b12)],C[(L₁₂)_(a12)-(R₁₂)_(b12)][R₁₇], Si[(L₁₂)_(a12)-(R₁₂)_(b12)][R₁₇],P[(L₁₂)_(a12)-(R₁₂)_(b12)], B[(L₁₂)_(a12)-(R₁₂)_(b12)], andP(═O)[(L₁₂)_(a12)-(R₁₂)_(b12)], X₂₁ is selected fromSi[(L₂₂)_(a22)-(R₂₂)_(b22)][R₂₆], P[(L₂₂)_(a22)-(R₂₂)_(b22)],B[(L₂₂)_(a22)-(R₂₂)_(b22)], and P(═O)[(L₂₂)_(a22)-(R₂₂)_(b22)], L₁₁ toL₁₃, L₂₁, L₂₂, and L₇₁ are each independently selected from asubstituted or unsubstituted C₃-C₁₀ cycloalkylene group, a substitutedor unsubstituted C₁-C₁₀ heterocycloalkylene group, a substituted orunsubstituted C₃-C₁₀ cycloalkenylene group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenylene group, a substituted orunsubstituted C₆-C₆₀ arylene group, a substituted or unsubstitutedC₁-C₆₀ heteroarylene group, a substituted or unsubstituted divalentnon-aromatic condensed polycyclic group, and a substituted orunsubstituted divalent non-aromatic condensed heteropolycyclic group;a11 to a13, a21, a22, and a71 are each independently selected from 0, 1,2, 3, 4, and 5; R₁₁ and R₁₂ are each independently R_(HT); R₂₁ and R₂₂are each independently selected from R_(HT) and R_(ET), and at least oneselected from R₂₁ and R₂₂ is R_(ET); R₇₁ is R_(ET); b11, b12, b21, andb22 are each independently selected from 1, 2, 3, and 4; R₁₃ to R₁₇, R₂₃to R₂₆, and R₇₂ to R₈₀ are each independently hydrogen, deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an aminogroup, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, aphosphoric acid or a salt thereof, a substituted or unsubstituted C₁-C₆₀alkyl group, a substituted or unsubstituted C₂-C₆₀ alkenyl group, asubstituted or unsubstituted C₂-C₆₀ alkynyl group, a substituted orunsubstituted C₁-C₆₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀cycloalkyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkylgroup, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, asubstituted or unsubstituted C₆-C₆₀ aryl group, a substituted orunsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstitutedC₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroarylgroup, a substituted or unsubstituted a monovalent non-aromaticcondensed polycyclic group, and a substituted or unsubstitutedmonovalent non-aromatic condensed heteropolycyclic group; b13 to b16 andb23 to b25 are each independently selected from 1, 2, 3 and 4; R_(HT) isa hole transport group; R_(ET) is an electron transport group; and atleast one substituent of the substituted C₃-C₁₀ cycloalkylene group, thesubstituted C₁-C₁₀ heterocycloalkylene group, the substituted C₃-C₁₀cycloalkenylene group, the substituted C₁-C₁₀ heterocycloalkenylenegroup, the substituted C₆-C₆₀ arylene group, the substituted C₁-C₆₀heteroarylene group, the substituted divalent non-aromatic condensedpolycyclic group, the substituted divalent non-aromatic condensedheteropolycyclic group, the substituted C₁-C₆₀ alkyl group, thesubstituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀ alkynyl group,the substituted C₁-C₆₀ alkoxy group, the substituted C₃-C₁₀ cycloalkylgroup, the substituted C₁-C₁₀ heterocycloalkyl group, the substitutedC₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀ heterocycloalkenylgroup, the substituted C₆-C₆₀ aryl group, the substituted C₆-C₆₀ aryloxygroup, the substituted C₆-C₆₀ arylthio group, the substituted C₁-C₆₀heteroaryl group, the substituted monovalent non-aromatic condensedpolycyclic group, and the substituted monovalent non-aromatic condensedheteropolycyclic group is selected from: deuterium, —F, —Cl, —Br, —I, ahydroxyl group, a cyano group, a nitro group, an amino group, an amidinogroup, a hydrazine group, a hydrazone group, a carboxylic acid group ora salt thereof, a sulfonic acid group or a salt thereof, a phosphoricacid group or a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenylgroup, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group; a C₁-C₆₀ alkylgroup, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀alkoxy group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid or a salt thereof, a sulfonic acid or a saltthereof, a phosphoric acid or a salt thereof, a C₃-C₁₀ cycloalkyl group,a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₁₁)(Q₁₂), —Si(Q₁₃)(Q₁₄)(Q₁₅), and—B(Q₁₆)(Q₁₇); a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkylgroup, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup, and a monovalent non-aromatic condensed heteropolycyclic group; aC₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, aC₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group,a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₂₁)(Q₂₂), —Si(Q₂₃)(Q₂₄)(Q₂₅), and—B(Q₂₆)(Q₂₇); and —N(Q₃₁)(Q₃₂), —Si(Q₃₃)(Q₃₄)(Q₃₅), and —B(Q₃₆)(Q₃₇);wherein Q₁₁ to Q₁₇, Q₂₁ to Q₂₇, and Q₃₁ to Q₃₇ are each independentlyselected from hydrogen, a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkoxy group, aC₆-C₆₀ aryl group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromaticcondensed polycyclic group, and a monovalent non-aromatic condensedheteropolycyclic group.